Sir Michael Fallon has resigned from his position as Defence Secretary, saying he had "fallen below the high standards" required of the armed forces.

"In the past I have fallen below the high standards that we require of the armed forces that I have the honour to represent," Sir Michael said in a statement announcing his departure.

The 65-year-old's resignation comes after he apologised for repeatedly placing his hand on a female journalist's knee during a dinner in 2002.

The incident involved journalist Julia Hartley-Brewer, who said she does not regard it as "anything other but mildly amusing."

On Tuesday, a spokesperson for the Conservative MP said he had "apologised when the incident happened 15 years ago and both Julia and now considered the matter closed."

Sir Michael's resignation comes amid swirling abuse allegations in Westminster.

Commons Speaker John Bercow met with senior parliamentary figures on the House of Commons Commission to plot reforms to allows victims of sexual abuse to report incidents "without fear" of reprisal.