WASHINGTON, March 9 (Reuters) - U.S. officials are planning to use Tuesday's meeting with a Ukrainian delegation in Saudi Arabia in part to determine whether Ukraine is willing to make material concessions to Russia to end the war, according to two U.S. officials.

The U.S. delegation will also be watching for signs that the Ukrainians are serious about improving ties with the Trump administration after a meeting between President Donald Trump and Ukrainian President Volodymyr Zelenskiy devolved into an argument last month, said one of the officials, who requested anonymity to preview the closed-door talks.

U.S. Secretary of State Marco Rubio will fly to Jeddah on Sunday for the bilateral talks with Ukrainian officials, who will be led by Andriy Yermak, a top Zelenskiy aide. Rubio is expected to be joined by National Security Adviser Mike Waltz and Trump's Middle East envoy, Steve Witkoff.

"You can't say 'I want peace,' and, 'I refuse to compromise on anything,'" one of the U.S. officials said of the upcoming talks.

"We want to see if the Ukrainians are interested not just in peace, but in a realistic peace," said the other official. "If they are only interested in 2014 or 2022 borders, that tells you something."

Trump expressed optimism about the talks. "We're going to make a lot of progress, I believe, this week," he told reporters traveling with him on Air Force One.