REHOBOTH BEACH, Del. (AP) — President Joe Biden and Vladimir Putin will speak Thursday as the Russian leader has stepped up his demands for security guarantees in Eastern Europe.

In announcing the call, the White House National Security Council spokeswoman said the two leaders will discuss "a range of topics, including upcoming diplomatic engagements."

The talks come as the U.S. and Western allies have watched the buildup of Russian troops near the border of Ukraine, growing to an estimated 100,000 and fueling fears that Moscow is preparing to invade Ukraine.

Secretary of State Antony Blinken spoke on Wednesday with Ukrainian President Volodymyr Zelenskyy.

Intelligence officials are worried Russia could launch an attack in the next few weeks.

U.S. and Russian officials have also agreed to sit down for security talks on Jan. 10, the Associated Press reported.

A Biden administration official says Russia requested Thursday's call, the news outlet reported.