If President Donald Trump approves the plans, such an effort would mark a new phase of the war that could be significantly more dangerous to U.S. troops than the first four weeks.

With President Trump urging Iran to "get serious" and make a deal before it's "too late," the tenor of the vague negotiations has gone from productive to fraught.

Meanwhile, Iran reacted to the possibility of U.S. troops on the ground by threatening to set them on fire.

By Mike Scarcella WASHINGTON, March 30 (Reuters) - A U.S. judge will hear arguments on Monday on whether the Pentagon has defied a court order protecting journalists’ access, in a closely watched clash over press freedom and executive power.