Policing the COP26 climate change summit in Glasgow could cost more than £200 million, Police Scotland’s chief constable has warned as he insisted the force must not be left out of pocket.

Iain Livingstone said the figure is a “very indicative” estimate of the cost of policing the UN summit in the city in November.

An estimated 90,000 people, including around 200 world leaders, are expected to take part in the conference.

READ MORE: COP 26: Nicola Sturgeon says UK government must cover security costs for Glasgow climate conference

Police also believe a climate change march planned to coincide with the summit could attract up to 500,000 demonstrators.

Speaking at a meeting of the Scottish Police Authority (SPA), Mr Livingstone said the cost of policing the summit highlights the “significance and magnitude” of the event.

Police officers will be brought in to Scotland from every force in the country, the SPA meeting was told, with the cost of housing them potentially running into tens of millions of pounds.

Mr Livingstone insisted: “There cannot be detriment to the funding of the police service in Scotland as a result of us delivering on the United Kingdom Government’s intention to host this conference on climate change in Glasgow.

“It is a fundamental point for me.

“I’m not being ridiculous in seeking full cost recovery, I am being absolutely legitimate for the public purse and for the police service.”

The Scottish Government has already insisted the UK Government should pick up the bill for policing the summit.

Mr Livingstone said COP26 will be “one of the biggest events ever hosted in the United Kingdom, with a significant number of heads of state expected to attend, as well as tens of thousands of delegates over a two-week period”.

He also warned it would attract “significant and legitimate demonstrations and protests”.

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Mr Livingstone said: “It will focus the attention of the world on the collective ability of Scotland to host a safe, secure and productive international conference with empathy and integrity.

“Policing will be central to that and the supporting police operation required is of itself a significant undertaking.

“Our early assessment indicates the policing cost of COP26 could potentially exceed £200 million in planning multiple site security, mutual aid and specialist support.”

He compared the conference to the massive security operations required at previous high-profile events in Scotland.

He added: “I know from personal experience having been involved in the Commonwealth Games, the papal visit, the G8 summit, quite how demanding and overwhelming they were at that particular time.

“The climate conference is of another magnitude in our assessment at this time.”

Meanwhile, Assistant Chief Constable Bernard Higgins told SPA members about some the challenges the event poses to police.

The summit runs from November 9 to November 20, but he said police will need to “stand up the full policing operation” at least two weeks before that.

The SEC in Glasgow will host the COP26 summit in November (Sandy Young/PA)

He said: “This is going to be without question the biggest policing operation in recent years. Even if you go back to the London Olympics it will be on parallel with that in terms of officers numbers, but the unique nature of this makes the threat level quite different.

“The absolute reality is if the safety and security plan is not in place, if it is not robust, if it is not going to deliver what it seeks to deliver, then the conference simply cannot happen because it would not be a safe and secure venue.”

Mr Higgins said protests at the conference would not just be about climate change, saying: “Some of the attending nations will attract protests because of their domestic policies, because of who they are.”

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He also spoke about the mass climate march that will “most likely” take place in Glasgow to coincide with the event, but could be held in Edinburgh.

Mr Higgins said: “We could reasonably anticipate in excess of 100,000 people, that’s a very conservative estimate because when it happened in Madrid it was reported it was 500,000 people that took to the streets.”

Mr Livingstone said his “key priorities” are to police the event “while of course ensuring that the citizens of Scotland are effectively protected and policed while we meet the policing requirements of the conference”.

But he added: “It is my professional opinion that any suggestion that the climate change conference will not impact on the wider community of Scotland is fanciful.”