Donald Trump's visit cost £18m, says National Police Chiefs' Council

British police chiefs say security for U.S. President Donald Trump's visit in July involved almost 10,000 officers and cost nearly 18 million pounds (US$24 million), making it the biggest police operation since riots swept England in 2011.

Almost 10,000 police officers from across the country were deployed to cover the events, performing more than 26,000 shifts, Sara Thornton, head of the National Police Chiefs' Council, said.

Police from around the country were drafted in to protect the President while he was in London.

Sara Thornton, who chairs the National Police Chiefs' Council, said that it was a "significant operation", with the U.S. president visiting four force areas and protests taking place in many others.

Among the large protests against Trump's visit were those held in London, Manchester, Glasgow and Belfast.

Thornton said the coincidence of the visit with the World Cup, hot weather, numerous events and festivals led to high demand on officers across the country.

"These demands affected local policing to differing degrees across the country with the host forces most impacted", the senior officer added.

"Despite the challenges, the hard work of officers and staff made sure that the public were kept safe throughout".

He managed to avoid most of the thousands of protesters opposed to his visit, with the demonstrations headlined by the appearance of a huge nappy-clad orange balloon dubbed "Trump baby".

Police in Scotland also arrested a paragliding protester, who flew close to Trump as he visited his Turnberry golf resort in Scotland.