WASHINGTON (NEXSTAR) -- The outgoing Biden administration is vowing to give the incoming Trump administration what it did not receive in 2021: a peaceful transition of power. "That's what the American people deserve," said President Joe Biden Thursday. "I assured him [Trump] that I direct my entire administration to work with his team to ensure a peaceful and orderly transition." The U.S. State Department and Pentagon echoed President Biden, saying the transition is vital to the country's security. "That's why it's so important for us to conduct a smooth, efficient and professional transition process," said State Department Spokesperson Matthew Miller.  "The department will make a calm, orderly and professional transition to the next Commander-in-Chief," said Deputy Pentagon Press Secretary Sabrina Singh. Biden administration officials said the transition is also important for foreign relations as world leaders brace for the return of President-elect Donald Trump. "There is one president at a time, and Joe Biden is the president," Miller said.  Miller said President Biden will continue to pursue ceasefire deals in the Middle East while Trump has urged quick ends to the wars in Gaza and Ukraine. "I am convinced that a quick end of the war would be a loss," said Ukrainian President Volodymyr Zelenskyy. Zelenskyy said he communicated that to Trump during his congratulatory call. "We would like a fair ending of the war," Zelenskyy said.  Russian President Vladimir Putin also weighed in on Trump's vow to quickly end the war. "This deserves attention at the very least," Putin said. "And I would like to take this opportunity to offer my congratulations on his election as President of the United States."  Trump has indicated he would also stop U.S. support for Ukraine. That's why President Biden wants to send out the remaining assistance, about $6 billion, before Inauguration Day. "We're going to surge and get that out there to Ukraine," said White House Press Secretary Karine Jean-Pierre.