A Tooting councillor has quit the Conservative party after claiming she endured three years of sexual discrimination.

Susan John-Richards believes she was ignored and overlooked for promotion because she is a woman.

However, the Tooting Conservatives have strongly denied her claims, stating they do not tolerate discrimination of any kind.

Other Tory insiders claim Ms John-Richards is disgruntled because she was deselected as a candidate for the next election – a claim she denies.

In a letter to the chief executive and director of administration at Wandsworth Council, Ms John-Richards outlines her claims of discrimination and writes: “It is with deep regret I am writing to you today to notify you as from today, September 8, 2009, I am no longer a Conservative councillor but an independent councillor, and I shall continue my term as such.

“Despite the fact I share similar ideologies to that of the Conservative party, I have been left with no option but to leave the group.”

Ms John-Richards said on Tuesday: “The hurt and disappointment that I feel has not only affected me but my constituents.

“I was always kept in the dark regarding my ward, always discriminated against and faced sexist remarks and actions.”

The single mother-of-two claims colleagues were briefed before her on ward issues. She also claims her requests to sit on certain committees were ignored and she was overlooked to move to a Tory safe seat.

Sources inside the party said she was unhappy after failing to be selected as a party candidate for the May 2010 election, but she rebuffed this claim.

According to her the problem was ongoing, but came to a head in February after the selections were announced. Ms John-Richards wrote to the national Conservative chairman, Eric Pickles, with a dossier of allegations in July, but has not yet received a response.

On Tuesday, she announced her decision to sit as an independent, although it is not known if she will stand in the next election.

Matthew Maxwell Scott, chairman of Tooting Conservatives, said: “Wandsworth Conservatives do not tolerate discrimination of any kind, and we will of course act should we receive any credible accusations that suggest otherwise.

“While it is regrettable Coun John-Richards has left the Conservative group, our remaining councillors are doing a great job ensuring residents get excellent services and the best possible value for money.”

Mark Clarke, Tory parliamentary candidate for Tooting, said: “I’m really sorry to see Susan go, we all care for her as a friend and look forward to her carrying on being the excellent councillor we know she is.”

Ms John-Richards is a former investment banker who was elected in 2006 to the Tooting ward, formerly a Labour safe seat.