In a survey of 186 firms which was carried out after the referendum, the Confederation of British Industry (CBI) and CBRE found two-fifths (41 per cent) intended to stick with their investment plans and half (50 per cent) planned to continue hiring.
However, a fifth (21 per cent) thought their investment might be lower than what they had planned for and just over one in ten (12 per cent) felt they may need to shave their headcount.
Lucy Haynes, CBI London director, said, although the figures indicate London firms are navigating the referendum uncertainty well, more reassurance from government might be needed to keep businesses booming.
"Many firms are still considering their response to the referendum, and in an increasingly competitive global race, they will be looking for a clear plan from the government and City Hall to maintain the openness of London's economy," said Haynes. "The government must confirm that those people from the EU who are already working in the UK can stay, and business stands ready to work together with politicians to make the capital grow and prosper."
Adam Hetherington, managing director in London of CBRE UK, added: "Business needs to pull together with policy makers to ensure the open for business message is communicated loud and clear to all corners of the globe. I have every confidence that by working together, we can ensure London remains the global city of choice."
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The CBI, along with the British Chambers of Commerce, the Federation of Small Businesses, the Institute of Directors and EEF, jointly wrote an open letter to government at the start of last month, urgently calling for issues arising from post-referendum uncertainty to be addressed.
Neither the Treasury nor City Hall has responded to City A.M.'s request for comment at time of writing.
There has been some concern regarding the rights of EU nationals who work in the UK since the Leave result was announced in June.
David Davis, the minister in charge of Brexit, has previously suggested a cut-off date might be put in place, whereby those arriving to the UK after a certain point would not be granted leave to remain status, if there was a surge in migrants from the EU.