“Russia’s forces are exhausted. The use of prisoners to reinforce, and now the mobilization of tens of thousands of inexperienced conscripts, speaks of a desperate situation,” Fleming said in an address to the Royal United Services Institute think tank in London.

“Far from the inevitable Russian military victory that their propaganda machine spouted, it’s clear that Ukraine’s courageous action on the battlefield and in cyberspace is turning the tide,” Fleming added.

Ukraine’s military has launched successful counteroffensives with the help of Western weapons, recapturing swaths of land previously held by Russian forces.

Ukraine war at a turning point with rapid escalation of conflict

Putin’s “decision-making has proved flawed,” Fleming said, and he has “little effective internal challenge” from Russia’s military and political elite.

“We know — and Russian commanders on the ground know — that their supplies and munitions are running out,” he said.

Britain’s Defense Ministry has become a daily source of information since Russia invaded its neighbor in February, churning out frequent bite-sized updates on social media analyzing Moscow’s military strategy and war effort.

The move to be more transparent with intelligence follows a strategically unusual decision by Western intelligence agencies, including the U.S. intelligence community, to publicly share information about Putin’s plans — although it ultimately was not enough to deter the invasion.

By speaking out, Fleming told the BBC in an interview early Tuesday, his agency hopes to “illuminate the threat” and encourage public trust. He cautioned that the United Kingdom is not writing off the threat from Russia. The last 24 hours have proved Moscow still has a “very capable military machine,” he said, referring to the strikes on dozens of Ukrainian cities Monday.

However, he added, Russia is running low on munitions and troops, and “it’s certainly running short of friends.”

Putin last month announced a partial military mobilization of as many as 300,000 reservists for what he still terms Russia’s “special military operation” in Ukraine. The decision sparked public panic, sending thousands of eligible men fleeing to borders and scrambling for flights to avoid being called up for deployment to the front lines.

Russians are “seeing just how badly Putin has misjudged the situation,” Fleming said. “They’re fleeing the draft, realizing they can no longer travel. They know their access to modern technologies and external influences will be drastically restricted. And they are feeling the extent of the dreadful human cost of his war of choice.”

Here are the nuclear weapons Russia has in its arsenal

A little more than a month after the war started, Fleming warned that Russian soldiers were low on morale and weapons and had, at times, refused orders and sabotaged their own equipment — painting a picture of chaos on Russia’s front lines even then.

Following this weekend’s attack on the Crimean Bridge, Moscow retaliated Monday by launching a wave of strikes that targeted parks, playgrounds and downtown areas far from the front lines, sparking outrage and killing at least 19 people, according to Ukrainian authorities.

Yet the strikes were cheered by backers of Putin. Viktor Bondarev, head of the foreign affairs committee of Russia’s upper house of parliament, called Monday’s strikes the beginning of “a new phase” and promised more “resolute” action to come.

Fleming also warned that Russia’s threats to use nuclear weapons to reverse its losses in Ukraine are “very dangerous” and could lead to a “catastrophe.” However, he stressed, so far there have been no indicators of their deployment, and Putin has been “staying within the doctrine of their use.”

This is consistent with the views of U.S. officials, who say they think it unlikely that Putin will carry out his threats. President Biden nevertheless warned last week that Putin was “not joking” and called his nuclear threats the most serious “prospect of Armageddon” in 60 years.

Strikes on Ukraine raise pressure on allies to send advanced air defense

The United Kingdom has three main intelligence services: MI6, the foreign intelligence service, popularized by the fictional spies James Bond and George Smiley; MI5, the domestic agency; and Government Communications Headquarters, known as GCHQ, the eavesdropping service. The entire intelligence community is famously secretive.

Fleming also spoke more broadly on global threats to security on Tuesday, singling out China’s bid to spread its influence through science and technology.

Saying this could be a “sliding doors moment in history,” Fleming accused China’s ruling Communist Party of seeking to create “client economies and governments.” He said China aims to bring countries into its sphere of influence by encouraging them to buy Chinese tech and incur what he called “hidden costs.”