Republicans have been deeply divided for years over immigration. The conservative base has been pushing to tighten the borders even as the party, hoping to keep its majority in Congress in November’s election, has been trying to reach out to Hispanic voters who are a growing force in American politics.

The issue has House Speaker Paul Ryan in one of the toughest struggles of his career.

On one side, Trump and conservatives in Congress insist on construction of a wall along the U.S.-Mexico border and a clampdown on both legal and illegal immigration. Centrist Republicans, meanwhile, are pressing for permanent protections that could lead to citizenship for the “Dreamers,” immigrants who were brought illegally as children to the United States.

Trump has signaled he would favor some steps to protect Dreamers, but has not specified how, and he also insists on a border wall.

Ryan has said he is working with the White House on a plan that Trump would sign into law, but after weeks of intense negotiations, he has not yet forged a deal. He told reporters on Thursday that members were still seeking a consensus but gave no timeline for action.

“It’s in complete flux,” said Republican Representative Patrick McHenry, a member of his party’s House leadership team.

Representative Carlos Curbelo, one centrist trying to force Republican leaders to hold votes on a bipartisan Dreamer bill along with more conservative immigration legislation, told reporters: “For us, a permanent fair solution, a bridge into the legal immigration system, is critical.”

He added that he did not know whether conservatives in his party would move his way. Trump has rejected a push by Curbelo and other moderate Republicans for a “Dreamer” deal, saying he would only back sweeping immigration legislation that met all his demands, including a border wall.

“Unless it includes a wall, and I mean a wall, a real wall, and unless it includes very strong border security, there’ll be no approvals from me,” Trump told Fox News. Any bill would also have to end a visa lottery program and curb visas for legal immigrants’ relatives, he added.

U.S. Speaker of the House Paul Ryan speaks to reporters at an enrollment ceremony for several House bills on Capitol Hill in Washington, U.S., May 24, 2018. REUTERS/Toya Sarno Jordan

Ryan, who plans to retire from Congress at the end of this year, has so far avoided pressure from both sides of his caucus to take up the contentious issue ahead of the November election.

As of Thursday, 23 House Republicans had signed a petition to force a wide-ranging debate and votes as soon as next month on a series of immigration bills. Signatures from two more Republicans along with support from most or all House Democrats would be enough to bring legislation to the House floor.

“What’s not going to happen is we’re not going to just spend time talking with no results. We have some deadlines,” said Republican Representative Mario Diaz-Balart, an early signer of the petition.

Democratic Representative Pete Aguilar, also a leader in the fight for a bipartisan Dreamer bill, said Republicans are arguing over whether Dreamers should win a pathway to citizenship, a key demand of Democrats and centrist Republicans.

“It doesn’t seem like they’re (Republicans) ever going to get to a bill in their caucus that gets to 218” votes needed for passage, Aguilar told reporters.