WASHINGTON (AP) — President Donald Trump's top national security aides sought to fend off accusations the president is too soft on Russia by declaring Wednesday that the U.S. will never recognize the annexation of Crimea and by postponing a second proposed summit between Trump and Russian leader Vladimir Putin.

As Secretary of State Mike Pompeo prepared to face questions about last week's Trump-Putin meeting from the Senate Foreign Relations Committee, the White House said Trump had opted against trying to meet with Putin this fall, as had been announced, and would instead wait until 2019. Nat...