The June 23 vote took many investors and chief executives by surprise, triggering the deepest political and financial turmoil in Britain since World War Two and the biggest ever one-day fall in sterling against the dollar.

“There’s something like a million people in the UK wake up each morning and then go to work for an American company in the UK,” said May, who is in New York to attend the United Nations General Assembly. She told reporters that she wanted to hear what issues they wanted addressed in the Brexit negotiations.

Chief executives from AECOM (ACM), Morgan Stanley (MS), BlackRock (BBN), Merck & Co (MERCK-CO-INC), Sony Pictures (SNE) and United Technologies Corp (UTX) will also be at the meeting, a spokeswoman for May said.

Get Data Sheet, Fortune’s technology newsletter.

The head of Thomson Reuters (TRI), the parent company of Reuters News, will attend, the spokeswoman said. After a closed meeting with major investors, May will see dozens of other executives at a wider reception.

Despite warnings before the vote that Brexit would shatter economic confidence, some positive economic data and Softbank’s (SFTBY) $32 billion takeover of Britain’s technology company ARM have stoked the perception that Britain could prosper outside the EU.

Still, May and her ministers admit they need to reassure investors from the United States, Japan, China and India that the United Kingdom and London, the only financial capital to rival New York, are still good places to make money.

The United States is the largest single inward investor into Britain, which currently attracts far more foreign direct investment than any other EU member.

Brexit Means Brexit

Some investors have called for clarity about how much access foreign companies based or operating out of Britain will have to the European market, a concern for some U.S. banks and manufacturers which sell into the EU from Britain.

Other issues include when and how Brexit will happen. May, who has repeatedly pledged that “Brexit means Brexit”, has so far said only that she will not trigger the formal EU divorce process before the end of this year.

“We’re going to be in a negotiation,” May said. “I’m very clear we’re going to go in there to get the right deal for the people of the UK. I’m going to be ambitious for Britain in the negotiations.”

U.S. President Barack Obama said this month that he wanted the Brexit process to be resolved in the least disruptive way possible, though both France and Germany face elections next year which could complicate the Brexit negotiations.

Goldman Sachs Is Warning Investors About Brexit-Related Trouble

Before the vote, some U.S. companies had warned that Brexit would complicate their lives and could cost jobs. Those included JPMorgan Chase (JPYYL) Chief Executive Jamie Dimon, who has 16,000 staff based in Britain.

British companies reduced their investment plans in the month after Britain voted to leave the EU, a survey by Lloyds Bank showed on Monday, a further sign the decision is likely to have a lasting impact on the economy.

Last month, the Bank of England left its forecast for British growth this year steady at 2.0% but cautioned that there might be little growth in the second half and sharply downgraded its forecast for 2017 to just 0.8% from a previous estimate of 2.3%.