Yell, the owner of Yellow Pages, said that revenues will be short of expectations as a result of weakening market conditions, sending its shares down more than 15 per cent.

The group, which also operates as Yell.com, said that it now expects full year revenue growth of 2 per cent in the year to March 31, compared with guidance in November for an improvement of about 3 per cent.

“We expect revenue to be just short of expectations, reflecting the toughening of market conditions experienced in recently closed sales canvasses in the UK,” said Yell in a statement.

The group said that it will give further guidance for the 2009 financial year as usual at the preliminary results in May.

The news came as a surprise to the City, as Yell is traditionally seen as an attractive defensive play in the UK media sector because of its relative resilience during downturns.

In the UK, Yell expects to benefit from more pricing flexibility this year as regulatory caps to which it has been exposed disappear.

By 2pm shares were down 52.5p at 277.5p at 1.30pm.