Media playback is unsupported on your device Media caption William Hague appears to mouth the words "stupid woman"

William Hague has said he meant no offence after being accused of calling a Labour MP a "stupid woman".

The foreign secretary was filmed apparently mouthing the words as Cathy Jamieson questioned his links to Conservative donor Aidan Heavey.

It came during a heated PM's questions dominated by a row over party funding.

When it was suggested he apologise, he said: "I mutter many things under my breath and I never intend any offence to any other honourable members."

Mr Hague was sitting behind David Cameron during prime minister's questions, as the PM continued his attacks on Labour's links with the trade unions - and Labour leader Ed Miliband hit back by attacking the Conservatives' links with the big business.

Wall of noise

The session became so rowdy, Speaker John Bercow complained about the "wall of noise" and later warned MPs of all parties to behave better.

Mr Hague's links with JCB - for whom he used to work as a political adviser - were questioned by shadow foreign minister Ian Lucas.

I never intend any offence to any other honourable members William Hague

Then Ms Jamieson, a shadow Treasury minister, stood up to ask Mr Cameron: "Perhaps you could tell the House whether [Tullow Oil chief executive] Mr Aidan Heavey's donations to the Conservative Party had any influence on the foreign secretary's intervention in his company's tax dispute?"

As Mr Cameron hit back, saying Conservative donations "do not buy votes at our party conference, they don't buy votes for our leader, they don't mean you can select candidates", Mr Hague sat behind him, apparently mouthing "stupid woman".

Later in the Commons, Labour's Fiona O'Donnell raised a point of order with the Speaker, saying: "We had the most heated and emotional PMQs of this session. While emotion may carry us all along, there are lines you insist we must not cross."

She said it had been reported by other MPs and the press that "the foreign secretary in response to a question asked by Ms Jamieson twice shouted the words 'stupid woman'.

"I know the foreign secretary to be a man who has done great good in his job and he is already regretting those comments, and I was wondering whether it would be appropriate for you to give him the opportunity to apologise to ensure that his reputation, but also the reputation of this place, is not damaged by such behaviour."

Mr Hague replied: "I mutter many things in this House. Others shout them rather louder than I do but I mutter many things under my breath and I never intend any offence to any other honourable members."

The deputy prime minister, Nick Clegg, was asked about the foreign secretary's remarks, during his weekly radio phone-in.

Mr Clegg conceded it "was not language one should use" but he said it was easy for MPs to get "carried away by the moment" in the chamber.

He said Mr Hague had made it clear he did not mean to cause any offence by his remarks, and insisted he was "one of the most polite and civilised politicians I deal with".