We've seen it before: Vladimir Putin doesn't react well to ultimatums. We saw it again, last night, in the Kremlin.

President Putin slammed European powers for talking to Russia "in a boorish manner and with the help of ultimatums".

He didn't go into detail. He didn't need to.

This was clearly his response to the ultimatum set by European leaders in Kyiv.

They had warned Moscow that if Russia didn't agree to an unconditional 30-day ceasefire from Monday, there will be more sanctions against Russia and more military assistance for Ukraine.

On Saturday, Sir Keir Starmer said that "if he [Putin] is serious about peace, then he has a chance to show it".

The Kremlin's response: we're serious, but we'll show it our way.

Putin's way (his counter proposal) is direct talks with Ukraine in Istanbul next Thursday.

But, crucially, no immediate ceasefire.

So, is the Kremlin's offer a serious peace initiative? Or is it simply an attempt by Moscow to play for time and to prolong the war? And, with this proposal, might Russia also be trying to split the Western coalition that is backing Ukraine?

Let's begin with a short, but key question: does Vladimir Putin want peace?

He claims he does. But peace only on Russia's terms.

Moscow suspects it has little to gain from a 30-day unconditional ceasefire, especially since the Russians believe they currently have the initiative on the battlefield in Ukraine.

But neither does Russia want to be seen as an obstacle to peace. It's keen to maintain a good relationship with the Donald Trump administration, with which the Kremlin has been working hard on improving ties.

If a US-Russia rapprochement continues, the Kremlin will be hoping for speedy sanctions relief and an economic boost.

By proposing direct talks in Istanbul, President Putin is sending a signal to the White House: "I am a man of peace."

But by not committing to an immediate 30-day ceasefire, the likelihood is Russia will continue the war, and push on to seize and occupy more Ukrainian territory.

The Kremlin leader's vague reference to "not excluding" that the Istanbul talks might lead to "new ceasefires" will be greeted with deep scepticism by Kyiv.

And when we're talking about war and peace, keep in mind that it was President Putin who ordered the full-scale Russian invasion of Ukraine in 2022.

This was his decision, one widely seen as an attempt to force Ukraine back into Moscow's orbit.

He didn't call it a war, though. He portrayed Russia's actions as a "special military operation".

Last night, though, Putin declared: "There is ongoing fighting, war. But we're offering to resume talks that were interrupted, and not by us. What's bad about that?"

The Kremlin may well be calculating that its offer of direct talks in Istanbul will drive a wedge between the US administration and European leaders.

Following Putin's announcement, President Trump hailed a "potentially great day for Russia and Ukraine" in a social media post, and promised to "continue to work with both sides to make sure that it happens".

Emmanuel Macron described Putin's offer as a "first step, but not enough." The French president also said "an unconditional ceasefire is not preceded by negotiations."

Putin announced his proposal in a late-night statement delivered inside the Kremlin.

I was among a small group of foreign journalists invited to join Russian reporters for what we were told would be a press conference.

We waited several hours for the event to begin. In the end, the Russian president took no questions. After delivering his statement he left the hall.