Ukraine is willing to become neutral and compromise over the status of the eastern Donbass region as part of a peace deal, President Volodymyr Zelenskyy said on Sunday.
It came even as another top Ukrainian official accused Russia of aiming to carve the country in two.
Mr Zelenskyy took his message directly to Russian journalists in a video call that the Kremlin pre-emptively warned Russian media not to report, saying any agreement must be guaranteed by third parties and put to a referendum.
Speaking in Russian, Mr Zelenskyy said: "Security guarantees and neutrality, non-nuclear status of our state. We are ready to go for it."
Volodymyr Zelenskyy
UKRAINIAN PRESIDENTIAL PRESS SER
Vladimir Putin
Reuters
But even as Turkey is set to host talks this week, Ukraine's head of military intelligence, Kyrylo Budanov, said Russian President Vladimir Putin was aiming to seize the eastern part of Ukraine.
Mr Budanov said: "In fact, it is an attempt to create North and South Korea in Ukraine."
Mr Zelenskyy has urged the West to give Ukraine tanks, planes and missiles to help fend off Russian forces.
He later said in his nightly video address that he would insist on the "territorial integrity" of Ukraine in any talks.
In a call with Mr Putin on Sunday, Turkish President Tayyip Erdogan agreed to hold talks this week in Istanbul and called for a ceasefire and better humanitarian conditions.
Ukrainian and Russian negotiators confirmed that in-person talks would take place.
Joe Biden
EVELYN HOCKSTEIN
It comes as American officials seek to clarify that the US does not have a policy of regime change in Russia, after US President Joe Biden said at the end of a speech in Poland on Saturday that Mr Putin "cannot remain in power".
US Secretary of State Antony Blinken said Mr Biden had simply meant Mr Putin could not be "empowered to wage war" against Ukraine or anywhere else.
After more than four weeks of conflict, Russia has failed to seize any major Ukrainian city and signalled on Friday it was scaling back its ambitions to focus on securing the Donbass region, where Russian-backed separatists have been fighting the Ukrainian army for the past eight years.
A local leader in the self-proclaimed Luhansk People's Republic said on Sunday the region could soon hold a referendum on joining Russia, just as happened in Crimea after the Kremlin seized the Ukrainian peninsula in 2014.
Crimeans voted overwhelmingly to break with Ukraine and join Russia — a vote that much of the world refused to recognise.
Mr Budanov predicted Ukraine's army would repel Russian forces by launching a guerrilla warfare offensive.
He said: "Then there will be one relevant scenario left for the Russians, how to survive."
Ukraine's foreign ministry also dismissed talk of any referendum in eastern Ukraine.
A spokesperson said: "All fake referendums in the temporarily occupied territories are null and void and will have no legal validity."