Commons leader Andrea Leadsom has been asked to make an urgent statement about tackling sexual harassment amid a series of allegations of inappropriate behaviour by MPs.
Theresa May has already called for tougher procedures to deal with MPs accused of harassment.
In a letter to Commons Speaker John Bercow, the PM said the Commons' disciplinary regime needed reforming.
Labour leader Jeremy Corbyn has offered to meet the PM to discuss it.
Mrs May also called for an independent mediation service, as she said the current regime lacked "teeth".
Sir Alistair Graham, the former chairman of the committee on standards in public life, warned against over-complicating procedures, but welcomed efforts to address complaints quickly.
He said it could be a "turning point" in tackling abusive behaviour at Westminster.
There are reports that lists of MPs accused of misconduct are circulating in Westminster.
Over the weekend, a Cabinet Office investigation was ordered into whether Conservative MP and international trade minister Mark Garnier breached ministerial rules after he admitted asking his secretary to buy sex toys and calling her "sugar tits".
And former Welsh Secretary Stephen Crabb was reported by the Sunday Telegraph to have admitted sending "explicit" messages to a 19-year-old woman after a job interview at Westminster in 2013.
Conservative MP Anna Soubry called for an urgent statement from Ms Leadsom on what can be done to ensure complaints are dealt with properly.
She said the idea of a new contractually-binding grievance procedure for all MPs and their staff, floated by Mrs May in her letter to the Speaker, was a good idea.
In her letter, Mrs May had said the current system for airing grievances – under which MPs were not bound by decisions from the Independent Parliamentary Standards Authority – was not fair on employees, many of whom were young and in their first job.
A Labour spokesman said: "There must be robust procedures inside as well as outside Parliament for dealing with abuse and harassment."
Mr Corbyn was ready to meet the speaker and the prime minister as soon as possible to strengthen those procedures and parliamentary-staff employment conditions, he said.
Liberal Democrat leader Sir Vince Cable signalled his support for the PM's initiative and said: "Parliament clearly needs improved procedures to respond to allegations of harassment."
Sex shop errand
Mr Garnier's former secretary Caroline Edmondson told the Mail on Sunday he had given her money to buy two vibrators at a Soho sex shop.
Ms Edmondson, who has since left to work for another MP, was also quoted as saying that on another occasion in a bar, in front of witnesses, he told her: "You are going nowhere, sugar tits."
The Mail reported that Mr Garnier admitted the claims, saying: "I'm not going to deny it, because I'm not going to be dishonest."
He told the paper: "It absolutely does not constitute harassment."
The incidents date back to 2010, before Mr Garnier was a government minister.
Married Conservative MP Stephen Crabb, who admitted meeting the 19-year-old woman "a few times," was quoted by the paper as saying he had been "foolish" but that there had been no sexual contact.
"I accept any kind of sexual chatter like this is totally wrong and I am sorry for my actions," the MP for Preseli Pembrokeshire said.
Mr Crabb resigned last year as work and pensions secretary following reports of a similar incident.
He did not respond to requests from the BBC for a comment.Let's