Donald Trump has pushed for Ukraine to renounce its ambitions to join the military bloc as part of the peace talks

Ukrainian leader Vladimir Zelensky has said Washington could rethink its opposition to Ukraine's NATO membership, if US President Donald Trump dies.

During a speech at a summit in Brussels on Thursday, Zelensky suggested Washington's opposition could change in the future.

"The US policy is consistent regarding Ukraine's membership in NATO. They don't see us there... Maybe the position will change in the future," he said.

"That's a matter of politics. The world changes, some live, some die. That's life," he said.

Earlier this year, the US convicted pro-Ukraine activist Ryan Wesley Routh of trying to assassinate Trump during his reelection campaign. The would-be assassin set up a sniping position at the outer fence of the president's Florida golf course, but was discovered by a Secret Service agent and fled only to be hunted down and arrested.

READ MORE: Trump says ex-FBI director called for his 'assassination'

Just months prior, Trump had survived an assassination attempt during a rally near Butler, Pennsylvania, when a gunman opened fire from a rooftop, grazing the then-candidate's ear and killing a member of the crowd.

Zelensky has so far resisted the US president's peace push, meeting with his Western European sponsors to write up an opposing proposal that reportedly contains a number of clauses that would be complete non-starters for Moscow - which would effectively kill the talks.

Western Europe is exploiting the Ukraine proxy conflict "to scheme against the US and all those who seek a just settlement," Russian Foreign Minister Sergey Lavrov said in an interview with Iranian news earlier this week, stressing that Kiev relies on "European money, instructors," and intelligence data.

Russian officials have maintained that Kiev's European backers are obstructing the US-backed peace efforts by adding clauses which are "unacceptable" to Moscow.

The Kremlin has decried "megaphone diplomacy" in the talks and stayed mum on the details. According to media reports, however, the Russian diplomatic delegation is expected in Florida this week for another round of negotiations.