OTTAWA -- Colleagues of all political stripes pilloried Don Meredith and urged the controversial senator to give up his Senate seat Friday following an explosive ethics investigation of his sexual relationship with a 16-year-old girl.

Sen. Peter Harder, the Liberal government's point man in the Senate, denounced Meredith's conduct as disturbing, unacceptable and an affront to Canadian standards of decency as he urged him to step down for the sake of his family.

Even those who once defended Meredith described being fed up, saying the only honourable thing for him to do was never set foot in the Senate again.

Harder said Meredith's resignation would ensure he didn't drag himself, his family, the woman he was romantically involved with and the Senate as a whole through the mud -- a fate Harder suggested Meredith should want to avoid.

Meredith, a married father of two and an ordained minister, has remained silent and has yet to respond to a request for comment.

It's unclear if the Senate has the authority to expel Meredith over the conduct detailed in Senate ethics officer Lyse Ricard's report.

The upper chamber has never turfed one of its own for any reason.

Most famously, it did in 2013 suspend three senators without pay for a parliamentary session -- Mike Duffy, Pamela Wallin and Patrick Brazeau. And in 1998, Andy Thompson retired after being suspended without pay for having barely set foot on Parliament Hill for years.

Several senators said they would like to see the Senate impose the harshest punishments possible against Meredith.

"I'd be very disappointed if he walked through the doors of the Senate again," said Conservative Sen. David Wells of Newfoundland and Labrador.

In a long-awaited report released Thursday, Ricard said Meredith failed to uphold the "highest standards of dignity inherent to the position of senator" and acted in a way that could damage the Senate itself.

The report found Meredith, 52, used his Senate cellphone for explicit chats, tried to help the woman land an internship on Parliament Hill, promised her a committee appointment and suggested he could help with her mother's permanent residency file.

Ricard also detailed sexually explicit online video chats between the two.

The report said Ricard believes Meredith had sex with the woman at least once before she turned 18, and twice after she turned 18. Meredith acknowledged he had sexual relations at least once with the woman after she turned 18, the report said.

In a letter attached to the report, Meredith told Ricard he deeply regretted what happened and vowed he would never breach the ethics code again.

Meredith was removed Friday from his leadership post within the independent senators' caucus. The head of the group, Sen. Elaine McCoy, said she spoke Friday with Meredith and recommended he resign.

"I think that would be the honourable thing to do," she said. "I'm sorry to say that."

The report is just the latest blemish on the Senate's reputation, which has taken a beating in recent years as a result of the Senate expenses scandal. Conservative Sen. Vern White, who also echoed calls for Meredith to quit, said the latest issue should not reflect on the upper chamber as a whole.

"Let's be very clear: Don Meredith owns his own actions," said White, a former police chief in Ottawa. "I'm not his keeper, and I don't think anyone else is. He owns it, and he'll have to deal with it. It has nothing to do with the Senate."

Appointed by former prime minister Stephen Harper, Meredith quit the Conservative caucus in June 2015 after the Toronto Star first reported on the relationship.

Speaking in Houston, Prime Minister Justin Trudeau said it's up to the Senate, not him, to decide what to do about Meredith. He did say, however, that politicians have to show themselves worthy of the public trust.