London-based Grimshaw, one of the UK's most respected firms, is shedding staff after a number of projects were delayed due to the results of the EU Referendum.
"Like many of our peers within the industry we have been experiencing delays on a number of planned projects due to the uncertainty caused by Britain's exit from the European Union," said the firm in a statement sent to Dezeen.
"Regrettably, this uncertainty in the market has lead us to make a small reduction in the headcount of our London office. We have always viewed our people as our greatest asset and this is not a decision that has been taken lightly."
According to The Architects' Newspaper, the studio is losing around 16 members of staff from its 300-strong workforce.
Irish architecture company O'Mahony Pike, which specialises in housing, has also announced that it will close its London office, with at least five job losses.
"We're not shutting down the company but we decided a full-time presence was too risky," managing director John O'Mahony told architecture site BDonline.
"Being an Irish practice operating in London, as things tighten up consideration will be given to local practices," he said. "It wasn't a spur of the moment thing, but Brexit was the straw that broke the camel's back."
The news comes just weeks after the Office for National Statistics posted figures that suggested the UK's construction industry was already heading for a recession before Brexit.
In April, May and June, the construction industry shrank by 0.4 per cent, despite an overall economic growth for the UK of 0.6 per cent.
Last week, construction body the Chartered Institute of Procurement and Supply (CIPS), reported that activity was now falling at its fastest rate since 2009 thanks to Brexit.
"Output and new business both declined for the first time in over three-and-a-half years, and at the fastest rates since early-2009," said CIPS in its latest update, which covered service supply and new business generated by its members in July.
"Consequently, employment in the sector was unchanged since June, ending a three-and-a-half-year period of uninterrupted job creation. The 12-month outlook for activity weakened sharply to the lowest since February 2009, linked to uncertainty regarding Brexit."
In July, UK firms Make and Sheppard Robson revealed they had cut jobs due to client uncertainty after the EU Referendum, and architecture giant BDP froze recruitment at its London office.
The Royal Institute of British Architects has called for a series of conditions to be implemented to protect the industry in the wake of the EU referendum result.
Architects and construction are often at the sharp end of an economic slowdown and the health of the industry is often used as a way to predict the onset of recession or economic boom.
In 2008, the global recession was preceded by widespread job losses among UK architecture firms.
But many have since diversified their businesses to try and protect themselves against a similar downturn, by opening international offices and spreading their expertise across multiple sectors rather than specialising in one area like housing.
Last month, leading architects including Amanda Levete and Alison Brooks joined Dezeen for a design summit to discuss ideas for helping the sector make the most of Brexit.
Some of these have now been submitted to create a manifesto to present to the government. Readers are invited to post their own suggestions in the comments.