Pre-tax profit at Wolseley, the materials producer, fell by a third in the five months to the end of December as a result of the global credit crunch.

In a trading statement this week it said trading profit during the period was down 25% despite a 2% rise in turnover. It added that it expected results to continue on a downward trend.

Steve Webster, the finance director, said: "We do expect markets in the United States to get worse until the full effects of the sub-prime crisis have been seen.

“The housing market will get worse before it gets better."

Wolseley said it made 10 bolt-on acquisitions over the period valued at £170m.