The smoking ban has hurt the pub business Punch Tavern's share price

In the 20 weeks to 5 January, the firm said like-for-like sales, which exclude the impact of new outlets, fell 2.2% in its managed pubs.

Food sales rose 1% and account for 39% of total sales in Punch's managed pubs.

Punch said it was too early to determine whether the smoking ban would have a long-term impact on trading.

But the firm said it still holds the view that the ban would have a positive effect on the industry over time.

"This is being borne out in Scotland where the ban came into force in 2006," it said.

The smoking ban was introduced in England and Wales on 1 July, 2007.

"After a satisfactory start to the year, trading over the last eight weeks has been more subdued in what has been widely acknowledged as a challenging period for the sector," the firm said.

"Whilst we remain cautious over the short-term outlook for the sector, the enduring popularity and appeal of the local community pub will continue."

As of 5 January, Punch managed 869 pubs and leased 7,581.

Shares in Punch Taverns closed down 35p, or 5.6%, at 586.5p.