President Joe Biden, eager for a bipartisan infrastructure deal, will welcome the Democratic and Republican senators crafting a $559 billion plan to the White House for talks Thursday, a crucial step toward moving his economic agenda through Congress. Members of the group of 10 senators directly involved in the negotiations expressed optimism that they were close to a deal with the president.

“We are very, very close,” Republican Senator Rob Portman of Ohio, one of the leaders of the Senate group, said after Wednesday’s round of discussions with Steve Ricchetti, counselor to the president and other Biden aides.

Although some of the details of the package for roads, bridges and other projects are still to be resolved, White House Press Secretary Jen Psaki said the talks had produced enough progress toward a potential agreement that the “president has invited the group to come to the White House tomorrow to discuss this in person.”

Senate Majority Leader Chuck Schumer said he and House Speaker Nancy Pelosi had agreed to try to hold votes on a bipartisan infrastructure package and a budget resolution setting up fast-track legislation with the rest of Biden’s $4 trillion economic plan in July.