“There is a real atmosphere of awkwardness between the U.S. and Ukraine on the front end of the Biden administration,” said Daniel Vajdich, a nonresident senior fellow at The Atlantic Council who specializes in Europe and Eurasia. “I do think there are very real, residual consequences from impeachment in that sense.”

The Ukraine portfolio is one of the trickier foreign policy issues the new president faces, as he juggles domestic political considerations, the promotion of an anti-corruption agenda globally and the U.S. response to a prospective Germany-Russia gas pipeline that, if completed, will please an ally, thrill an adversary and deprive Ukraine of billions of dollars in revenue annually.

So far, Biden’s been deliberate in his approach. In his nearly 50 days in office, he has spoken to close to two dozen world leaders, from allies to adversaries to frenemies. But Ukrainian President Volodymyr Zelensky, a key partner on the frontlines of the battlefield with Russia — and the man who unwittingly found himself in the Trump impeachment spotlight — is still waiting his turn.

“There is merit to having Zelensky sit and wait his turn for a call,” said one former U.S. official who remains close to the Biden administration. “He is not struggling with all his might to fight corruption. In fact, pro-Russian oligarchs in Ukraine have gained immense power since Zelensky took over. So there needs to be tough love with Zelensky when that one-on-one conversation does happen.”

A senior administration official emphasized that America’s commitment to “Ukraine’s sovereignty, territorial integrity and Euro-Atlantic aspirations is rock solid,” and discouraged the public from reading too much into the fact that Biden hasn’t called Zelensky yet.

“I know he looks forward to speaking to President Zelensky to discuss the ambitious agenda at the heart of our revitalized partnership,” the official said. She added that both Defense Secretary Lloyd Austin and Secretary of State Antony Blinken have spoken to their Ukrainian counterparts.

Zelensky tried to lay low during Trump’s first impeachment, working hard to stay out of the domestic political turmoil. But he did tell reporters at one point during the saga that it was not wise to block aid to a strategic partner at war with a major western adversary. The Biden administration last month released half of the $250 million in security assistance appropriated by Congress — the other half is contingent upon Ukraine’s progress on anti-corruption reforms that are negotiated in advance with Kyiv.

“We have a lot of catching up to do to show our commitment to an anti-corruption agenda and to the rule of law,” said one former top Zelensky aide who still advises the government.

Zelensky is also not oblivious to the political forces at work, having witnessed how Biden’s overt calls for reform in Ukraine were weaponized in the last two years of the Trump administration. In a now-infamous phone call in July 2019, Trump tried to bribe Zelensky into investigating Biden’s dealings in Ukraine in order to derail Biden’s election campaign. Trump was impeached over the episode. But his allies have continued trying to use Biden and his son’s work in Ukraine as a political cudgel.

“You would think the Ukrainians would have learned that pursuing a phone call with the president of the United States has in the past turned out not to have been a good idea,” joked former U.S. Ambassador to Ukraine William Taylor. “Bad things came out of that last phone call.”

The former Zelensky aide said that there is broad recognition in Kyiv that Washington is taking a “tough approach to reforms” in Ukraine.

It’s not an unusual strategy for Biden, who pushed hard for anti-corruption reforms in Ukraine while he was vice president. In late 2015, he began agitating for Ukraine to remove its top prosecutor, Viktor Shokin, and threatened to withhold up to $1 billion in U.S. aid until Shokin was fired. It was that threat that was used by Trump-allies as evidence that he was trying to assist his son’s business dealings — a charge that made little sense, since at the time Shokin was not investigating the gas company Burisma, on whose board Hunter Biden sat.

Though President Biden has yet to call Zelensky or engage directly with the Ukrainians in any formal way, he has signaled to Kyiv that its reform initiatives must continue. In one significant step this month, the State Department sanctioned the powerful Ukrainian oligarch Ihor Kolomoisky, in what both Ukrainians and American foreign policy experts perceived as a not-so-subtle hint that Zelensky should do more to rein in the oligarchs himself.

“I do think it is important for Zelensky to be able to represent to the [Ukrainian parliament] that U.S. support has not all of a sudden become no-strings-attached,” said Sen. Chris Murphy (D-Conn.), a member of the Senate Ukraine Caucus. “They are very different strings than those that existed during the Trump administration, but we still expect there to be reforms in order to have us be a friend, partner, and advocate.”

Oleksandr Danylyuk, who served as Zelensky’s national security adviser until late 2019, said that Ukrainains heard the message of the Kolomoisky sanctions loud and clear. “This is the signal from the U.S. to act,” he said. “Zelensky has all the tools necessary to tackle the oligarchs if he actually wants to.”

Case in point: Ukraine’s recent decision to sanction the powerful Ukrainian businessman Viktor Medvedchuk, a close friend of Russian President Vladimir Putin who also serves as a senior official for the pro-Russian Ukrainian political party For Life.

U.S. and European officials have broadly viewed the Medvedchuk sanctions as a step in the right direction. But the U.S. wants to see a broader de-oligarchization campaign, and it’s still unclear whether the sanctions were the first step toward such a campaign or whether they were simply the result of a domestic power struggle.

“If I were sitting in the White House, I would see that in Ukraine there has clearly been some backtracking on anti-corruption efforts” that were spearheaded during the Obama administration, Danylyuk said.

One area of concern for the Biden administration has been the Ukrainian parliament’s efforts to exert greater control over the country’s National Anti-Corruption Bureau — a bill passed by the lawmakers last month would empower them to fire NABU’s director Artem Sytnyk.

Another bad sign from the administration’s perspective has been Kyiv’s recent row with the International Monetary Fund, which suspended a $700 billion payment to Ukraine earlier this year until the government makes more progress in reforming its justice system, removes natural gas subsidies for Ukrainian households and re-establishes the independence of its central bank.

“After a very fast start, I think Zelensky’s reform agenda has predictably stalled,” Murphy said. “In particular, NABU has to be empowered and Sytnyk has to be able to operate independently — people need to fear him and his operation. So I think it is important for us, early on, to make it clear that if reforms proceed in 2021 at the same pace that they did in 2020, it’s going to be hard to make the case to Congress to continue support for Ukraine.”

Taylor, who served as the U.S. charge d’affaires to Ukraine after the former ambassador, Marie Yovanovitch, was forced out of her position by the Trump administration, said he believes that “Ukrainians ought to be reassured by this new administration,” not only because it sanctioned Kolomoisky — “one of the most destructive oligarchs in Ukraine” — but also because of the statement Biden released last month committing to never recognize Russia’s purported annexation of Crimea.

“You don’t get presidential statements like that every day,” Taylor said.

But Crimea is just one of several thorny issues. Some Ukrainian government officials are nervous about this administration’s approach to Nord Stream 2, a major Germany-Russia gas pipeline under construction that could deprive Kyiv of up to $1 billion annually and give Russia more control over the region. Lawmakers had expected that a report from the State Department last month would identify more targets for Nord Stream 2 sanctions, as required by law. But the report only identified two Russian vessels involved in the project that had already been sanctioned by the Trump administration.

The former Zelensky aide said a chief concern internally was that the Biden administration would prioritize its relationship with Germany — which wants the Nord Stream 2 construction to continue — at the expense of Ukraine’s security.

The senior administration official pushed back on that, saying that “we are continuing to look at entities that may be involved in sanctionable activities and will take necessary follow-on steps from there.” The official added that Biden sees the pipeline “as a clear example of Russia’s aggressive action in the region, which provides the means to use a critical natural resource for political pressure and malign influence against Europe.”

Taylor, the former ambassador, acknowledged that there is a policy tension within the new administration between wanting to repair the U.S. relationship with Germany, which was battered by Trump, and protecting European energy security and Ukrainian sovereignty. But he noted that allies disagree all the time while remaining friends and partners and argued that countering Russian President Vladimir Putin depends largely on strengthening Ukraine.

“There needs to be a return to a recognition that if Ukraine succeeds, then Mr. Putin fails,” he said. “If Ukraine succeeds in becoming a normal European country — a values-oriented, market-based, part of Europe — then Putinism fails. I think President Biden understands that.”