NEW ORLEANS (AP) — Lawyers for hundreds of people who sued Merck & Co. over its withdrawn painkiller Vioxx are challenging a key provision of a proposed $4.85 billion settlement that requires lawyers to advise all or none of their clients to accept the deal.

Plaintiffs lawyers who negotiated the settlement said Friday they expect the challenge will be withdrawn, as a similar one filed last month was.

In court papers filed Thursday, lawyers for about 2,600 plaintiffs asked a U.S. District Court judge in New Orleans to rule that portions of the settlement can't be enforced in all states because it prevents lawyers from giving clients their "independent professional advice."

The lawyers, based in Missouri and Illinois, also are asking U.S. District Judge Eldon Fallon to set a date for Merck to make final settlement payments.

A Merck spokesman said the company would comment later Friday.