MALE Tory MPs were told off today by the Commons speaker for "boorish" and "stupid" behaviour for shouting down women when they speak.

John Bercow intervened to admonish rowdy Conservatives after Labour's Emily Thornberry was attempting to ask Cabinet Office minister David Lidington about why the UK Government refuses to lower the voting age to 16, as indeed the Scottish Government has done for Holyrood and council elections.

But as she tried to press Lidington, Tory MPs could be heard shouting in the background, prompting Bercow to make his disapproval clear.

He said: "Order! Order! I'm sure it'll not have escaped public notice, and it is rather a sad irony, that when a woman is addressing the House, quite a lot of noisy, boorish and in one case a rather stupid individual trying to shout the right honourable lady down.

"Cut it out."

Lidington was standing in at the dispatch box at Prime Minister's Questions for Theresa May who is on a visit to China, and as convention dictates Thornberry, who is shadow foreign secretary, stood in for Labour leader Jeremy Corbyn.

A robin could be seen watching the exchanges in the Commons chamber, perched near a side gallery where visitors were based.

Thornberry concentrated her questions on the themes of votes for women, women's representation in politics and lowering the voting age to 16.

She opened her questioning by noting: "I am the only Emily elected since 1918 and he is one of 155 Davids.

"The women behind me on these benches represent one quarter of all the women elected in the last 100 years but it's still not good enough."

She asked Lidington how female representation could be increased in the Commons, with the minister initially saying he was delighted to see her in place when "no fewer than 97 members of her frontbench have either been sacked or resigned" since Corbyn became Labour leader.

Lidington agreed all political parties want to encourage more female candidates to come forward, saying Labour had a "bit of catching up to do" given there have been two female Tory leaders.

But Thornberry shot back: "I've got to say, if the party opposite is so proud of having a female leader, why are so many of them trying to get rid of her - and why has she had to run away to China to get away from them?"

During the exchanges the Labour frontbencher put it to Lidington that there's "no principled objection" to votes at 16, and called the Tories and the DUP a "coalition of cavemen" for resisting it.

Lidington replied Thornberry should stop watching the Flintstones, saying there are a number of organisations "working hard to get young people used to the idea they should take an interest in current affairs" and exercise their vote responsibly.

To protests from Labour MPs, he then urged Thornberry to "grow up" on this question.

Later in the session the SNP accused the Government of being "prepared to make everyone poorer" and called for leadership over Brexit.

Ian Blackford, the party's leader in Westminster, spoke out after leaked analysis showed the economy would not grow as much as current forecasts predict under a number of scenarios for the UK's withdrawal from the EU.

Lidington told Blackford that Britain would leave the single market and customs union as a matter of legality.

He added that the Prime Minister wanted to negotiate a new partnership with the EU to continue frictionless trade.

"I must say I'm surprised at the minister because there's not a question of legality. We're going to be in a transitional deal, we'll still be in the single market with the EU," said Blackford.

"This is a Government in crisis and an international embarrassment.

"The Chancellor, the Scottish Secretary, the Scottish Conservatives, the Home Secretary have all supported membership of the single market.

"Despite this, the Government is still prepared to make everyone poorer. Where is the leadership?"

Lidington replied: "The leadership which he wants was set out very clearly both at Lancaster House and then again in Florence, and the Prime Minister will be making further speeches on these issues in the weeks and months to come.

"But can I just say to him that the most important single market to the people of Scotland is the single market of the United Kingdom."