MP Paul Burstow knew of allegations of sexual impropriety by the former chief executive of the Liberal Democrats, it has been claimed.

In a Channel 4 investigation, broadcast on Thursday night, women who had worked for the Liberal Democrat party claimed the party's former election strategist, Lord Christopher Rennard, had inappropriately touched and propositioned them.

Its been alleged that Sutton and Cheam MP Paul Burstow was told about one allegation but failed to act on the woman’s concerns.

Alison Smith, a politics lecturer at Oxford University, claimed that six years ago when she was an aspiring Lib Dem activist she and a friend were invited back to Lord Rennard's house after dinner in central London.

She said: "He just very suddenly got up and plonked himself between us and then he started moving his hands down our backs and places where they had absolutely no business being."

She said she had reported the incident to Paul Burstow MP for Sutton and Cheam, who was then the party’s chief whip, however she heard nothing.

She added: "[Paul Burstow] listened very patiently and sounded very concerned and then basically said he would do something about it and be in touch, but he never was."

Lib Dem leader Nick Clegg has asked Tim Farron, the party president, to conduct an immediate review into the party’s procedures for dealing allegations of harassment, including an examination of how allegations made in the past have been handled.

Mr Burstow was unable to comment on the allegations other than along the lines of the official party statement which said: “An internal investigation into the specific allegations raised by Channel 4 has begun under the party’s disciplinary procedures.

“There are a number of questions that have been raised and our reviews will ensure we properly address all of them.

“We will not tolerate harassment in our party and we urge anyone to contact the chief executive or use our confidential whistle-blower procedure if they have issues they wish to raise as a result of Channel 4’s report.”

Lord Rennard has strongly denied the allegations but has temporarily stood aside from the House of Lords to avoid embarrassment to the party.