Britain should be willing to suspend arms sales to Saudi Arabia and Yemen if the two countries fail to reach a solution in their growing conflict, a senior MP has said.

Former Labour minister Keith Vaz said positive diplomatic moves by Britain were being "undermined" by its arms sales to Saudi Arabia, with £3.3 billion of aircraft and bombs sold to the regime over the past year.

The Leicester East MP said Britain's relationship with Saudi Arabia "will have to be looked at" if it is found to have breached human rights laws in Yemen.

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In an adjournment debate in the Commons, Mr Vaz told MPs the United Kingdom had already drafted a UN Security Council resolution calling for an end to hostilities, the need for investigations into human rights violations, and the re-start of negotiations between the two countries.

This was the catalyst for Saudi Arabia and Yemen agreeing on Tuesday to a 72-hour ceasefire, Mr Vaz said.

But he said good diplomatic work by the Government "is being undermined by the £3.3 billion of aircraft and bomb sales to Saudi Arabia in the 12 months from March 2015".

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Mr Vaz went on to say: "We can still be the honest broker. That means putting pressure on all sides, including those who receive British support.

"Can the minister tell us whether or not the United Kingdom is prepared to sanction the Yemeni and Saudi governments through withdrawing support, suspending arms sales or otherwise, if they allow the next round of negotiations to fail?"

International Development Minister Rory Stewart responded that the Government takes arms sales "very seriously", and a recent Committee on Arms Export Controls report on the matter was "divided" as to the best course of action.

He added: "We continue to monitor very, very carefully all actions of international humanitarian law, although that is not a prime responsibility of my department.

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"We will continue to put pressure on all parties to this conflict to support the current peace."

Mr Stewart also confirmed that no British military personnel are embedded in the current Saudi operation.

He did acknowledge, though, that the British military continues to provide training and capacity support, which includes statements about international humanitarian law, to the Royal Saudi Air Force in a general capacity.