Berkeley Group's first-half pretax profit fell 25.7%, the UK house-builder said, as it warned about an uncertain short-term outlook as people put off house purchases ahead of Britain's exit from the European Union.
Pre-tax profit fell to £401.2m in the six months ended October 31, from £539.9m a year earlier.
Berkeley said its short-term outlook was uncertain because of the ongoing Brexit negotiations and a number of other unspecified headwinds in its London and the South East markets.
"This uncertainty affects sentiment and confidence which has a consequential adverse impact on investment levels and transaction volumes with a number of developers withdrawing from these markets," the company said in a statement.
UK house prices have grown for most of the past 25 years.
But they have softened in the past year as the government struggled to find its way through Brexit talks and speculation mounted that thousands of financial and other jobs could leave the country.
The days of London house price rises hugely outpacing inflation will not be returning anytime soon, even if Britain and the EU strike a Brexit deal, the vast majority of economists and analysts polled by Reuters said in November.
Berkeley reiterated today that Britain's housing market lacked urgency and was constrained by high transaction costs and limits on mortgage borrowing.
The company delivered 2,027 homes in the first half, down from 2,190 last year.
Berkeley, however, raised its full-year pretax profit forecast by more than 5%.