WASHINGTON — Illegal immigrants might face around a 10-year wait to become legal permanent U.S. residents under sweeping immigration overhaul legislation taking shape in the Senate, negotiators said Thursday. That’s shorter than some current wait times though longer than some advocates might like.

Democratic Sens. Dick Durbin of Illinois and Robert Menendez of New Jersey discussed the timeline in a roundtable meeting with Hispanic-focused media. The senators and their aides emphasized that nothing has been agreed to and the timeline could change.

The timeline refers to how long someone would have to wait in a new provisional legal status before qualifying for permanent residency and a green card. The legislation is expected to immediately grant provisional legal status to many of the estimated 11 million illegal immigrants now in the country, but they couldn’t get green cards until the border has been secured, and they would have to meet criteria including learning English and paying fines.

The process “is likely to be in the range of 10 years, I say in the range because we have not nailed this down,” Durbin said. He said various factors go into the timeline, including the need to establish border security first, something Republicans have insisted on.

Menendez said a 10-year wait would not be inordinate considering that under current law many illegal immigrants face a 10-year prohibition against returning to the country if they leave.

“If you think about it, under current law there is a 10-year bar, so the bottom line is you would have to wait anyway,” Menendez said. “The difference is you would get the opportunity to be here, to come forward, to work, to travel, and in doing so to earn your pathway” to citizenship.

A green card is the crucial first step toward citizenship although it takes up to five years for a green card holder to become a citizen under current law. So if it takes 10 years to get a green card, the total wait time for citizenship could be closer to 15, advocates fear.

“We understand that bipartisan lawmaking requires compromise. But we think waiting 15 years for a chance to become a citizen is too long,” said Frank Sharry, executive director of America’s Voice. “We will continue to fight for a clear, direct and inclusive path to citizenship that has achievable requirements and a more reasonable time frame.”

The emerging legislation, which faces an uncertain future in Congress, is expected to require illegal immigrants to petition for citizenship behind those already attempting the process. That means some length of wait would be inevitable, although experts said lawmakers could shorten the wait times by making more green cards available.

“Going to the back of the line is inevitably a lengthy process because of current backlogs for which there have been insufficient numbers of visas in current law,” said Doris Meissner, a senior fellow at the Migration Policy Institute.

Wait times vary greatly under current law for people to get green cards, depending on factors including what country they’re from. For Mexicans trying to join family members legally in the U.S. the wait time can be 12 to 15 years, Meissner said.

The exact process and length of time for an illegal immigrant to get a green card is just one of many contentious issues being discussed by Durbin, Menendez and six other senators in a bipartisan group trying to finalize an immigration bill by spring. Even if they succeed the bill faces a tough road in the Democratic-controlled Senate and an even tougher one in the Republican-led House.

Sen. Charles Schumer, D-N.Y., another negotiator on the legislation, emphasized no decisions have been made. “Nothing has been decided yet with respect to the path to citizenship,” Schumer said through a spokesman in response to the comments from Durbin and Menendez.

Also Thursday, union leaders announced a 14-city campaign to mobilize support for immigration overhaul plans.