The Senate passed a $1.5 trillion stimulus package on Wednesday night, setting the stage for a $2.5 billion showdown over a looming government shutdown.
President Trump said in a tweet that he had signed the measure, and the Senate passed it quickly.
He also said he would veto the measure if it were to go to the president’s desk.
Trump is pushing for a partial shutdown, but Senate Democrats have threatened to stop him.
The Senate also approved a $6.3 billion bill to help small businesses, a major Democratic demand in the shutdown fight.
It includes tax relief for the middle class, as well as tax breaks for oil companies, airlines, banks and pharmaceuticals companies.
The measure, which was approved on a party-line vote of 52-48, will provide a $25 billion windfall to small businesses.
It also aims to keep federal agencies from closing.
The House approved a spending bill to fund the government through December.
It included a $5.5-billion extension of unemployment benefits for Americans who have been out of work for more than six weeks.
Democrats in the Senate, however, are pushing to keep the benefits for the unemployed.