Donald Trump is expected to return to the UK in December for a Nato summit, prompting fresh plans for protests against the US president.

The controversial leader, who has repeatedly clashed with the military alliance, will meet with heads of state in London, Nato secretary general Jens Stoltenberg announced on Wednesday.

It will be Mr Trump’s second visit to Britain since his election, having jetted in amid numerous protests last July and leaving behind a policing bill of more than £14 million.

Mr Stoltenberg said that “allies have agreed” that the next Nato heads of state and government will be held in London in December.

Theresa May “looks forward to welcoming all Nato leaders”, her official spokesman said when asked about Mr Trump’s next visit.

In a statement, the Prime Minister said the meeting will be an important moment in deciding how to “modernise” the alliance in the year of its 70th anniversary.

Nato said the meeting is foreseen as a summit of heads of state but it is up to individual nations to determine who to send.

A date and venue is yet to be determined but the president’s UK critics quickly eyed-up the opportunity to protest.

The Liberal Democrats said they will be “front and centre to protest his visit”, while the Green Party tweeted “we’ll be there to greet him”, adding a defiant gesture.

The Campaign for Nuclear Disarmament pledged to organise London protests against “Trump’s nuclear warmongering”, as well as against Nato.

Policing Mr Trump’s four-day visit in July cost more than £14.2 million, figures obtained by the Press Association showed this week.

There were marches against his presence across the UK, as he met the Queen at Windsor Castle, was hosted by Mrs May at her country retreat Chequers, and played golf at one of his resorts in Scotland.

While the proposed visit in December would follow a different schedule, there will be concerns over the cost of securing the controversial leader.

On Wednesday, the Prime Minister said the challenges of today are “very different” from those when the alliance established its first headquarters in London in 1949.

“The UK has played a central role throughout Nato’s history as it has adapted to deal with new and complex threats to our security,” Mrs May added.

“So, as we pay tribute to the service men and women who have worked so hard over so many years to keep us safe, December’s meeting is an important opportunity to determine the steps we must now take to modernise the alliance and ensure its continued success.”

Mrs May’s official spokesman made clear that any visit by the US president for the Nato summit was separate from the planned state visit by Mr Trump, for which no date has yet been fixed.

The invitation to a state visit was extended by Mrs May during her visit to Washington shortly after Mr Trump’s inauguration in January 2017 and the spokesman said it remains on offer.

Announcing the summit, Mr Stoltenberg said: “The meeting in London will be an opportunity for allied heads of state and government to address the security challenges we face now and in the future, and to ensure that Nato continues to adapt in order to keep its population of almost one billion people safe.”

Mr Trump has repeatedly railed against Nato as he successfully pressured allies to pledge billions more in defence spending.

As recently as Tuesday in Washington, he said in his State of the Union address that the US had been “treated very unfairly by friends of ours, members of Nato” over a period of years.

The summit was announced as Macedonia came a step closer to becoming the alliance’s 30th member when allies signed a key document at a ceremony in Brussels.