But once he had publicized the plans for Ms. Pelosi, who is second in line to the presidency, to travel to a war zone, security arrangements for the trip were jeopardized, sending congressional officials scrambling for a way to salvage it.
Mr. Trump’s letter arrived as lawmakers who were to have accompanied Ms. Pelosi were in a bus near the Capitol about to head to Andrews Air Force Base for their departure, and it led to a frenzied round of clandestine contingency planning late Thursday, as the speaker huddled in her office with the lawmakers, aides and security officials hatching a plan to use commercial flights. But given the State Department’s heightened warnings and indications that the plans were leaking out, Ms. Pelosi decided early Friday to delay the visit altogether.
“Why would Nancy Pelosi leave the Country with other Democrats on a seven day excursion when 800,000 great people are not getting paid,” Mr. Trump asked in a message on Twitter before Ms. Pelosi’s office had announced that she was postponing the trip. It had actually been scheduled for six days, departing late Thursday and returning on Tuesday.
Mr. Hammill said that Ms. Pelosi and the other lawmakers scheduled to take the trip, including Representative Adam B. Schiff, Democrat of California and the chairman of the Intelligence Committee, and Representative Eliot L. Engel, Democrat of New York and the chairman of the Foreign Affairs panel, were planning to use to trip to conduct oversight and thank American troops.
“The Congress has a constitutional responsibility to conduct oversight in the war zone where our men and women in uniform are risking their lives every day,” he said.
As the bad blood and reprisals continued between the president and the speaker, the White House announced a new policy banning all official, taxpayer-funded congressional travel for the duration of the shutdown, unless lawmakers had direct approval from Mr. Trump’s team.
“Under no circumstances during a government shutdown will any government owned, rented, leased or chartered aircraft support any congressional delegation, without the express written approval of the White House chief of staff,” Russell T. Vought, the acting director of the Office of Management and Budget, wrote in a memo Friday announcing the policy change.