Vladimir Putin has said Russia should have invaded Ukraine earlier, in a national address spanning more than four hours.
Russia began the conflict with its neighbour in February 2022 and at his annual televised news conference, Mr Putin claimed the war has made Russia "stronger".
The decision to invade "should have been made earlier" he added, before stating Russia could have "prepared for it in advance and more thoroughly".
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He claimed: "Russia has become much stronger over the past two or three years because it has become a truly sovereign country.
"We are standing firm in terms of economy, we are strengthening our defence potential and our military capability now is the strongest in the world."
The news conference also saw Mr Putin address a possible end to the war, as he said he is "ready to compromise" in possible talks with US President-elect Donald Trump.
He said he was open to meeting Mr Trump, who has pledged to negotiate a deal to end the conflict, saying the two would "have things to discuss".
"Politics is the art of compromise. We have always said that we are ready for both talks and compromise," he said.
"Soon, those Ukrainians who want to fight will run out, in my opinion, soon there will be no one left who wants to fight," he continued. "We are ready, but the other side needs to be ready for both negotiations and compromises..."
Any talks should be based on "the situation on the ground", Mr Putin added, referring to conditions he previously laid out.
He has previously demanded Ukraine withdraw its bid to join NATO and asked it to recognise Russia's gains. Both Kyiv and the West have rejected those demands.
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Mr Putin also said Moscow will only be ready to sign a deal with Ukrainian President Volodymyr Zelenskyy if he secures re-election.
Mr Zelenskyy's five-year term technically came to an end in May but was extended due to martial law.
In response to a question about Moscow's new hypersonic missile, he mockingly challenged the US to a "high-tech duel" to see whether Western tech could protect Ukraine from a strike using the weapon.
With a dry smile, he said: "Let them select a target, possibly in Kyiv, put their air defence assets there and we shall strike it with the Oreshnik [missile]. Let's see what happens."
Zelenskyy responds to Putin's comments
Mr Putin's comments have already sparked a strong response from Mr Zelenskyy, who is currently in Brussels for a summit on the Ukraine war.
In response to the duel suggestion, Mr Zelenskyy replied: "Do you think he is a sane person?"
In a show of solidarity with Ukraine, a number of EU leaders at the summit repeated a variation of a common mantra - nothing about Ukraine without Ukraine, nothing about security in Europe without Europeans.
Luxembourg's Prime Minister Luc Frieden said: "We need to stand with Ukraine, and every step [...] needs to be taken with Ukraine and in the presence of the European Union.
"The future of Ukraine is decided in Europe and not elsewhere."
(c) Sky News 2024: Russia should have invaded Ukraine 'earlier' says Putin - as he addresses possible peace talks