by Kristen Johanson

PHILADELPHIA (CBS) — Philadelphia will be in the political spotlight this week, as GOP lawmakers meet for their bi-annual retreat in Center City.

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President Trump will make an appearance, as well as British Prime Minister Theresa May, who will address Republican lawmakers on Thursday.

“Teresa May is going to be the first leader to address the Republican meeting here in Philadelphia, that has never happened before,” said Howard Silverstone, board member with the British American Business Council of Greater Philadelphia, which helps bolster and improve British businesses here in the Philadelphia area.

He says May will likely speak about the economy and trade relations, as Britain braces to leave the European Union.

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“The US is Britain’s largest trading partner, outside of the European countries, so if you don’t take the EU as a block, and you just take each European country individually, the US is larger than all of those for the UK,” said Silverston. “In 2016, American exports to the UK were over $50 billion, and imports from the UK were close to that as well.”

May is also expected to speak about international security issues, like how to combat ISIS and the future of NATO.

The Prime Minister will meet with Trump on Friday in Washington, D.C. — just a week after his Presidential Inauguration.

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“For a British Prime Minister to meet with a new President so quickly, it shows the unique relationship our two countries have,” said Silverstone.