Zelenskyy unsure about Trump's potential actions on Ukraine war if elected

Ukrainian President Volodymyr Zelenskyy has said he could not predict what Donald Trump would do if elected to a second term as US president in November, adding he did not know Trump well but hoped America's support to Kiev would not change.

"I don't know him very well. I don't know. I had meetings with him, and we had good meetings when he was the president... but we didn't (go) through the war with him," Zelenskyy said, speaking during an event at the Ronald Reagan Institute in Washington.

"I can't tell you what he will do, if he will be the president of the United States. I don't know."

Trump argued before he could end the war in Ukraine in one day; however, Russia's UN envoy, Vassily Nebenzia, rebuffed his claims.

"The Ukrainian crisis cannot be solved in one day," Nebeznia said, referring to Trump's claims of ending the war once elected.

Zelenskyy urges US to aid Kiev before November

Zelenskyy also urged US political leaders in Washington not to wait for the outcome of America's November presidential election to move forcefully to aid his country against Russia's invasion.

"Everyone is waiting for November. Americans are waiting for November, in Europe, Middle East, in the Pacific, the whole world is looking towards November and, truly speaking, (Russian President Vladimir) Putin awaits November too," Zelenskyy said, speaking on the eve of the NATO summit.

"It is time to step out of the shadows, to make strong decisions ... to act and not to wait for November or any other month."

Earlier, White House national security adviser Jake Sullivan outlined a series of measures to strengthen US and NATO support for Ukraine.

NATO will announce in the coming days a new military command in Germany led by a three-star general for training and equipping Ukrainian troops, and appoint a senior representative in Kiev to deepen Ukraine's relationship with the alliance, Sullivan told a conference on the defence industry sponsored by the US Chamber of Commerce.