Chocolate retailer Thorntons Plc posted a 36 percent drop in full year profits on Tuesday because of sluggish high street demand and said Chief Executive Peter Burdon intended to step down.

Pretax profit crumbled to 5.2 million pounds in the year to June 24, from 8.1 million the previous year.

Thorntons said like for like sales fell 3.7 percent for the year, although the performance had improved in the second half of the year when like for like sales fell 1.8 percent.

In terms of current trading, the hot weather in July resulted in a decline in chocolate sales, partly offset by high ice cream sales. In August and early September, sales were in line with our expectations, Chairman John von Spreckelsen said in a statement.

Sales at the group's own 367 UK stores fell 5.3 percent to 127 million pounds over the year largely due to a bad Christmas and a reduction in the number of outlets.

Hoping to reverse the downward trend, Thorntons said it would invest 1 million pounds on upgrading and refurbishing its shops. It also planned to look at buying new sites for stores in the southeast of England as well as cafes in retail parks.

On a positive note, demand for chocolates over the company's Internet site grew 6.4 percent over the past 12 months to 5.5 million pounds.

The company said it planned to expand further its Internet operations, enabling customers to create their own box of chocolates with the click of a mouse.

Other future plans to boost business included exploring opportunities of sourcing packaging and ingredients from countries in eastern Europe and Asia rather than just in Britain, Thorntons said.

Von Spreckelsen said Burdon would stay on as chief executive until a successor was appointed.