Mr. Buffett said at the annual shareholders’ meeting that he wanted to turn over the reins to Greg Abel at the end of the year. Earlier, he criticized Trump’s trade policies.

The mobilization could indicate that Israel is preparing to shift its tactics in its fight against Hamas.

As G.O.P. lawmakers have largely ceded power to President Trump, they are also pushing the bounds of a little-known statute to undo federal rules — and potentially undermining the filibuster.