A Philadelphia city councilman is set to offer a compromise version of his bill to ban plastic bags that he hopes will assuage opposition from the mayor and some his colleagues, as well as the concerns of environmental groups.

Councilman Mark Squilla plans to introduce an amendment to the bill next week, which would allow a final vote by the end of the year.

The legislation would ban most retailers from packaging their wares in single-use plastic bags. Opposition to the bill centered not on the ban on regular plastic bags, but rather on a planned fee on other retail bags, including paper and thick plastic bags that are considered reusable.

The proposed compromise would ban regular plastic bags immediately, but delay the fee for one year. During that year, the city would measure whether bag use has decreased, and if not, the fee would be imposed. Squilla said he hasn’t determined what the fee would be, but a previous version of his bill included a 15-cent levy per bag.

The compromise would bring back on board some environmental groups in the city, who dropped their support after Squilla removed the fee from the original legislation to get it approved by a Council committee amid opposition from Mayor Jim Kenney’s administration.

“It’s not everything we wanted, but the administration was opposed to an initial fee without seeing how it would work,” Squilla said. “So we’re trying to put in the bill to say, ‘All right, let’s see how it works without a fee.’ And again, not everybody’s happy.”

The legislative push comes as a growing number of cities and states across the country are implementing laws aimed at limiting single-use bags. In Philadelphia, three previous attempts by City Council to limit plastic bag use have failed.

Similar legislation in other cities has shown a fee is needed to encourage consumers to bring their own bags, environmentalists have said. Without a fee, they said, the legislation was unlikely to reduce waste in the city.

But it remains unclear whether Squilla’s last-minute efforts to form a consensus will be successful. Retailers may lobby against the bill if it doesn’t immediately include a fee to defray the cost of providing paper or compostable bags, which are more expensive than plastic.

Council would need to approve the amendment at its meeting next Thursday for the bill to pass at its final meeting of the year on Dec. 12.

David Masur, executive director of Penn Environment, said he and other environmentalists would support the latest compromise.

“There’s a lot of unknowns given that we’ve waited until the eleventh hour to see if there’s a way to get this done," he said.

Another uncertainty is how Harrisburg will react. Republicans, who control the legislature, added a provision to this year’s state budget prohibiting cities from banning plastic bags for one year while the state studies the potential economic and environmental impacts. Lawmakers could still make that prohibition permanent.

Squilla had the support of both retailers and environmental groups for his original proposal, which would have banned single-use plastic bags and instituted a fee for thicker plastic or paper bags.

But after the Kenney administration, which had initially supported the bill, disclosed its opposition, Squilla removed it to get the bill through the Licenses and Inspections Committee. That move angered a coalition of environmental groups.

A Kenney spokesman this week said the administration had no comment on the bill. Squilla said the amendment is still being drafted and hasn’t yet been circulated to administration officials and his Council colleagues.

Masur said he’s hopeful the final legislation will also further restrict which bags are covered by the ban. The bill currently bans bags that are less than 2.25 mils thick, the standard for single-use bags. But after the fee was removed, environmentalists worried the bill would inadvertently increase plastic bag waste because retailers could offer thicker plastic bags free.

Masur said he hopes the final legislation will have restrictions so that “no plastic bag can really meet the standard, therefore you’ll have to use a heavy-duty, woven, reusable, canvas-type bag."