The federal government began reopening Wednesday night after President Trump signed into law a spending package that narrowly passed the House, ending the longest shutdown in the nation’s history.

“With my signature, the federal government will now resume normal operations,” Mr. Trump said as he signed the legislation alongside Republican House leadership and business executives.

Earlier, the House voted 222 to 209 on Day 43 of the shutdown and days after eight senators in the Democratic caucus broke their own party’s blockade and joined Republicans in allowing the spending measure to move forward, prompting a bitter backlash in their ranks. It was the first time the House had held a vote in nearly two months, after an extended recess during the shutdown.

Some programs like food stamps, or the Supplemental Nutrition Assistance Program, could be restored within hours, while other effects could take longer to unravel.

Mr. Trump used the bill signing to attack Democrats for what he called “extortion,” blaming them for harm inflicted on air travel and the loss of paychecks for federal workers. Polling, however, shows most Americans blame Republicans for the shutdown.

“People were hurt so badly,” said Mr. Trump, whose administration fought in court to not fund food stamps, tried to fire thousands of federal workers and threatened to withhold back pay from others during the shutdown.