A senior Tory MP is understood to have clashed with security at the Conservative Party conference, prompting a lockdown of part of the venue.

Sir Geoffrey Clifton-Brown was involved in what a doorman described as a “small misunderstanding” at the International Lounge in the conference centre.

Police said an attendee tried to enter the lounge without the relevant pass, leading security staff to intervene.

It is understood Sir Geoffrey was trying to enter the room with a guest.

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The “misunderstanding” led to a lockdown of some areas, including the press room, at the Manchester Central Convention Centre for around 20 minutes.

This is the press scrum after a police incident occurred at Tory conference. Nobody allowed in here where it's said to have taken place. pic.twitter.com/ASBAmtx4OV

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The Cotswolds MP told the PA news agency: “I’ve got nothing further to say about it. I don’t want to comment on it, really.”

A staff member guarding the door of the International Lounge said the incident was sparked by a disagreement.

“It was a small misunderstanding,” the man said.

Greater Manchester Police said in statement: “At around 1.45pm on Tuesday 1 October 2019, an attendee to the Conservative Party Conference attempted to enter the International Lounge area of the conference without the relevant pass.

“Security staff intervened and resolved the situation without any breach of security occurring.” 

A Conservative Party spokesman said: "The incident was totally unacceptable.

"Geoffrey has been asked to leave Conference and we are establishing all of the facts to see if further action is necessary.

"We will always adopt a zero tolerance approach to any inappropriate behaviour towards our hardworking staff," he added.