Shares in PizzaExpress plummeted last week after the surprise resignation of the company's chief executive, Ian Eldridge.

Insiders hinted that Eldridge, who will be paid compensation of about £142,000 in respect of this year's contract, left partly because he felt he had been at the company long enough after 18 years and partly because of disagreements with his chairman, David Page.

However, some observers believe the pressure to go must have been stronger than that. Nigel Popham, at Teather & Greenwood, said Eldridge had probably been pushed and the Questor column in The Daily Telegraph says he was probably, "at least, partly pushed".

Page, who now moves from chairman to chief executive denied Eldridge had been forced out. Page said three new people had been put on the board and the job had essentially been split into three. Page said Eldridge felt the role of running the group's international operations was not enough for him.

No explanation was given for Eldridge's departure after 19 years with the company. PizzaExpress said its chairman, David Page, will now take on the role of chief executive, while its deputy chairman, Nigel Colne, becomes non-executive chairman.

The news came as PizzaExpress unveiled pre-tax profit for the six months ended December 31 up 12% to £21.8m before exceptional items, after turnover rose 16% at to £103.8m.

Like-for-like sales at the main PizzaExpress brand were up 3% on the same period in 2000, rising from 2% in the first quarter to 4% in the second. However, at Cafe Pasta, which the company said had a "disproportionate" number of outlets in Central London, results were more badly hit by the slump in restaurant trade that followed the events of September 11. The first quarter saw like-for-like sales fall 4%, which was only partly mitigated by a rise of 2% in the second half, leaving overall like-for-likes in the division down 1% on the same half in 2000.

The company said it had closed its two San Marzano outlets in the United States after two years at a cost of £700,000, because both restaurants were sustaining losses and producing negative like-for-like sales.

The company said it still believed the UK and Ireland can accommodate at least 500 traditional PizzaExpress restaurants, against the current 287, and 100 Cafe Pasta restaurants against the current 14.

PizzaExpress opened its first airport restaurant in Terminal 2 at Heathrow, followed by its second in the South Terminal at Gatwick. Both restaurants are trading ahead of expectations and it plans to open in more airports. More than a dozen other openings during the period included a 160-seat restaurant and a PizzaExpress To Go quick service counter at the Olympia Exhibition Centre in London.

The company plans to open at least 40 restaurants in 2002, plus five new PizzaExpress To Go restaurants, including one at Paddington mainline station, London in April..

It said Sainsbury's now sell PizzaExpress products in more than 300 of its UK stores, and sales of chilled pizza, garlic bread and doughballs are now averaging more than 120,000 units a week. In late December 2001 a range of PizzaExpress chilled pizza, garlic bread and doughballs were launched in Great Pacific Place and Parknshop superstores in Hong Kong. The company said early sales are promising, and "further opportunities are being evaluated in the region".

Tempus in The Times says it would be a mistake to get over-concerned about Eldridge's departure, pointing out the reputation of Page and the company's "excellent" track record. It speculates a merchandising deal with Tesco could be on the cards at some stage, after the success of a deal with Sainsbury's to sell PizzaExpress-branded food.

But the Questor column in The Daily Telegraph advises investors to "take a slice of Ask instead".

The City Diary in The Times says Eldridge will remain as wicket-keeper of the PizzaExpress cricket team. Hugh Osmond, who helped to float the company, still opens the batting.