Shares in the company were down 22.8 percent at 289 pence in early trading on the London Stock Exchange. The stock was the worst performer on the pan-European Stoxx 600 <.STOXX>.

Restaurant Group, which operates chains like Chiquito and Frankie & Benny's, has seen its performance hurt by the growth of online shopping, resulting in lower footfalls and higher level of competition from food-led pubs and other branded restaurant chains in the UK.

The company had said in January that it was more cautious than previously on its 2016 outlook.

Restaurant Group now expects like-for-like sales to be down between 2.5 percent and 5.0 percent for the full year, resulting in profit before tax in the range of 74-80 million pounds.

The company reported a profit before tax of 86.8 million pounds in the previous year.

Restaurant Group said its chief financial officer, Stephen Critoph, would leave the company with immediate effect and that the board had commenced the search for a new CFO.

The company said it had begun a comprehensive review of its operating strategy, which includes its property portfolio, site roll-out programme, brand positioning and overheads.

(Reporting by Aastha Agnihotri in Bengaluru; Editing by Sunil Nair and Anupama Dwivedi)