WASHINGTON -- Republicans on the Senate Judiciary Committee accused their GOP colleagues working on a bipartisan immigration bill of operating in secret, saying in a letter Friday that "the time for transparency has come" and pushing for briefings and full hearings before any votes.

In response, Sen. Marco Rubio, R-Fla., a member of the Senate group developing a sweeping bill that could be released as early as next week, said he agreed on the need for hearings and planned to brief all Senate Republicans next week. He disputed the claim that the immigration bill process has been more secretive than any other and said he's worked to incorporate suggestions from all senators.

The back and forth was the latest dispute over the timing and process of legislation that would usher in the most sweeping changes to immigration law in a quarter century and put an estimated 11 million immigrants living in the country illegally on a path to citizenship. Some Republicans have been pushing for an open process with multiple hearings before the Senate Judiciary Committee, while some Democrats accuse them of trying to slow-walk the matter to death.

In the clubby Senate, openness about negotiations and timing can be important to satisfy the concerns of individual senators and ensure that legislation stays on track. And the dispute is a sign of how contentious the bill is becoming even before its release.

The issue has become a particular focus for Rubio, who's proceeding with caution as he tries to act as a bridge between the immigration group and conservatives suspicious of its plans, who have begun to complain that Democrats are trying to ram the legislation through without sufficient debate.

"Your group has secretly met for months and not consulted with members of the committee about major changes to our nation's immigration laws," top Judiciary Republican Sen. Chuck Grassley of Iowa wrote along with Sens. Jeff Sessions of Alabama, Ted Cruz of Texas and Mike Lee of Utah. "We believe it is time for you to discuss the status of your negotiations, disclose what concessions have been made and provide details."

The letter went to Rubio and Sens. John McCain and Jeff Flake of Arizona and Lindsey Graham of South Carolina.

Rubio released a letter back that stressed his agreement on an open process.

"This proposal will be a starting point," Rubio wrote. "As members of the committee of jurisdiction I expect you to have ample opportunity to review, comment and amend as you see fit ... You can expect that I will continue to defend the rights of every senator, myself included, to conduct this process in an open and detailed manner."

• Read more articles by ERICA WERNER

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