Thorntons has reported strong sales growth over Christmas despite the continued weakness of its own store sales.

Against a weak festive trading period in 2012, the confectioner said total sales for the 14 weeks to 12 January increased by 5.4% to £88m.

The increase was driven by the strength of sales through the supermarkets, which increased by 26.4% to £34.7m. International sales also did well, growing 69% to £2.5m.

However, Thorntons stores continued to struggle. Like-for-like store sales declined 1.3% and total store sales dropped 9% to £40.9m following the closure of 27 shops over the past year.

Franchise sales also suffered, falling £1.1m to £3m, following the collapse of Clinton Cards and online sales were also down 15% to £4.8m, after a re-launch of the website was delayed. 

“We are pleased with the overall progress made during this key trading period,” said Thorntons CEO Jonathan Hart. “Our seasonal lines have sold through well, resulting in stock levels lower than anticipated and below last year at the period end.”

Thorntons said profits were in line with expectations and ahead of last year.

“This was a good Christmas for Thorntons, and the continued outperformance of commercial, together with some encouraging signs in private label and international, are evidence that the strategy is working,” said Investec analyst Bethany Hocking.

Shares in the confectioner dropped 5% to 43p in early trading.