Story highlights John Conyers is the longest currently serving member of the US House

The House Ethics Committee opened an investigation into Conyers last week

(CNN) House Democratic Leader Nancy Pelosi on Thursday called on Rep. John Conyers to resign following allegations of sexual harassment against the Michigan Democrat.

"The allegations against Congressman Conyers, as we have learned more since Sunday are serious, disappointing and very credible," Pelosi said at her weekly news conference. "It's very sad and the brave women who came forward are owed justice. I will pray for Congressman Conyers and his family, and wish them well. However Congressman Conyers should resign."

The California Democrat added, "No matter how great a legacy there's no license to harass or discriminate. In fact it makes it even more disappointing."

Conyers, 88, is the longest currently serving member of the US House of Representatives.

Pelosi isn't the only Democrat calling on Conyers to go. Rep. Jim Clyburn, the assistant Democratic leader and highest-ranking African American in the House, is now also calling on Conyers to resign, according to a source close to Clyburn.

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