President Trump’s July trip to the United Kingdom cost local law enforcement approximately $23.8 million — or £18 million — for security to manage London’s large protests and those around the country, a new report says.

In total, an estimated 250,000 people participated in a London protest, one of the largest Britain has ever seen. Additionally, almost 10,000 police officers were designated to monitor the protests all over the United Kingdom.

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"This was a significant operation with the president visiting four force areas and protests taking place in many others," said Sara Thornton, head of the National Police Chiefs' Council, an association of U.K. law enforcement.

"The majority of forces had to cancel officers' rest days and extend the length of their shifts," said Thornton. "Despite the challenges, the hard work of officers and staff made sure that the public were kept safe throughout."

The security costs were significantly higher than former President Barack Obama’s trip to the United Kingdom in 2016, which was estimated to cost approximately $2.2 million.

Trump had tea with Queen Elizabeth II during the trip, and also met with Prime Minister Theresa May.