U.S. President Donald Trump’s special envoy Keith Kellogg said in Kyiv on Monday that officials are “working very, very hard” on efforts to end the three-year war between Russia and Ukraine, as a lack of progress fuels doubts about whether a peace settlement could be on the horizon.

Officials are “hoping to get to a position where, in the near term, we have, with a lack of a better term, security guarantees” that address Ukraine’s fears of another invasion by Russia in the future, Kellogg said.

“That’s a work in progress,” Kellogg said of the potential security guarantees after attending Ukraine’s annual National Prayer Breakfast along with politicians, business leaders and diplomats.

A week ago, Trump said he had set in motion arrangements for direct peace talks between Russian President Vladimir Putin and Zelenskyy.

But Russian officials have signaled that such a summit won’t happen any time soon.

Trump said Friday he expects to decide on next steps in two weeks if direct talks aren’t scheduled.

A stream of high-ranking visitors to Kyiv in recent days reflects concerns around the U.S.-led peace drive.

Speaking at the same event, Ukrainian President Volodymyr Zelenskyy said "the battle between good and evil continues".

"Russia continues to attack, continues to knock us down, to destroy us. This must be stopped," Zelenskyy told the crowd.

"I believe that together we can achieve this. We will achieve peace, a peace that will be lasting, that will endure. That is what all our prayers are for today. And they will certainly be heard."

AP Video shot by Alex Babenko