Why Jo Cox would not want MPs to stop meeting the public

It comes as a memorial fund set up in memory of Mrs Cox, who died after being shot and stabbed in her constituency of Batley and Spen on Thursday, has raised £1m in just three days.

Mr Mitchell said: “I do not believe she would want this vile and unspeakable act to change the open and accessible relationship we enjoy with our constituents.

“All of us take the advice of our local police in protecting those who work and support us.

“Thankfully, the record shows these attacks are as infrequent as they are disgraceful.”

A single white rose was laid on Mrs Cox’s empty seat in the House of Commons as MPs gathered to pay tribute to her yesterday.

MPs also wore white roses in memory of the Yorkshire-born mother-of-two.

Labour’s Rachel Reeves, whose constituency of Leeds West is just a few miles away from Mrs Cox’s, broke down in tears as she remembered her friend of 10 years.

She told the Commons: “Batley & Spen will go on to elect a new MP, but no one can replace a mother.”

She added: “She died doing the job that she loved in the place that she loved, representing the people that she loved.”

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Jo Cox tributes: “More united than divided”

A series of events are being organised around the world to pay tribute to Mrs Cox on what would have been her 42nd birthday tomorrow.

Mr Mitchell, a former international development secretary who first met Mrs Cox in 2006, also paid tribute to the late MP.

He said: “She was Labour to her fingertips but restlessly dismissive of party political manoeuvring which she saw as a barrier to progress.

“Making common cause with a crusty old Tory she and I became co-chairs of the all-party friends of Syria. And she was brave – her energy and effectiveness were an inspiration.”

He added: “Jo would want us in this House to redouble our efforts to resolve the greatest catastrophe of our age – the crisis in Syria where the lives of more than 11 million people have been ruined while the international community has shown itself disorganised, ineffective and supine.”

The Sutton Coldfield MP recalled their meeting with the Russian ambassador, when the “5ft bundle of old fashioned Yorkshire common sense” dressed the envoy down for his country’s ‘cruelty and cynicism’ in Syria.

There has been speculation that the killing of Mrs Cox – which took place in the street outside her constituency surgery – may lead to tighter security for MPs.

MPs were due to meet with police and parliamentary authorities yesterday to discuss their security in the wake of Mrs Cox’s death.

Home Secretary Theresa May was to co-chair the meeting, where representatives of the Metropolitan Police and Independent Parliamentary Standards Authority were expected to answer questions from MPs.

A Whitehall source said the purpose of the session was to ensure that MPs were fully briefed on the security options available to them. Education Secretary Nicky Morgan has previously said she was considering installing a panic button in her office after Mrs Cox’s death.

The Education Secretary said her colleagues regularly received abuse and she thought security measures would become more common.

Speaking previously, Mrs Morgan said: “Panic buttons are going to become a lot more common.

“I’m thinking of having one fitted in my office.”