CHICAGO (AP) — London’s mayor sought Friday to reassure American investors, tourists and students that his city will remain open for business despite his country’s decision to withdraw from the European Union.

Sadiq Khan said during a visit to Chicago that London is demanding a seat at the table when the British government begins formally negotiating its exit from the EU, and will ensure the deal is a “good one.” London’s first Muslim mayor, the son of Pakistani immigrants, came with another message for America, telling reporters that Republican presidential nominee Donald Trump was playing “into the hands of extremists” with his hostile rhetoric toward Muslims.

But Khan and his delegation of London-based entrepreneurs were primarily focused on trying to ease concerns over a British exit from the EU during their five-day trip to Montreal, Chicago and New York. Uncertainty over whether Britain will continue to have access to the EU’s single, market has left financial experts worried about a big hit to the country’s business sector.

“One of the reasons I’m here is to reassure friends in America, businesses, students, tourists, innovators, investors that London is open,” Khan said.

Chicago Mayor Rahm Emanuel signed a technology-partnership agreement with Khan Friday and said he wouldn’t have done so if he had doubts about London’s future status as a global city.

The two men took a boat tour of the Chicago River, cruising past skyscrapers including one bearing Trump’s name in 20-foot tall letters. Emanuel showed off the city’s new Riverwalk, a pedestrian and recreational path lined with cafes and businesses. They dropped in on a discussion about entrepreneurship at a Chicago tech hub known as 1871.

Emanuel, who is Jewish, also planned to take Khan to his synagogue.

“You have in Chicago a mayor of Jewish faith,” Khan said. “We have in London a mayor of Islamic faith. I think that message — our friendship — is a message that is bigger than the Brexit vote.”

On Thursday, Khan delivered a speech at the Chicago Council on Global Affairs on the importance of social integration in diverse cities, saying a failure to do so makes it easier for “terrorists to radicalize our young people.” Afterward, he told reporters that Trump plays to extremists.

“We shouldn’t inadvertently play into the hands of extremists who say it’s not possible to be somebody who is a mainstream Muslim and hold Western liberal values,” Khan said.