In a brief statement, the board confirmed that it was in preliminary talks with "a number of parties" that may or may not result in an offer being made. It said the board was reviewing its "strategic options" both on a stand-alone and a third-party basis.

The company has been trying to sell its frozen food business

United Biscuits makes such well-known brands as Jaffa cakes, Penguins, and KP snacks, but has been struggling financially in the past few years.

Shares in the company soared as dealers hoped for a premium on its share price. They ended nearly 21% higher in London at 228p, valuing the company at £1.1bn.

Analysts predicted that the company could be sold for as much as £1.3bn ($2.15bn).

They speculated that U.S. private investment firm Hicks Muse Furst & Tate, which specialises in underperforming European brands, might be interested in the perennial underperformer.

The BBC's Maria Brown: "Several potential buyers are hungrily eyeing the company"

At the weekend, UB had been linked with chocolate manufacturer Cadbury Schweppes in newspaper reports.

Cadbury Chief Executive John Sutherland said in July the company was interested in using the proceeds of the sale to boost its confectionery business.

"Everyone likes the idea that United is going to be taken over, and Cadbury is cash rich following its disposal to Coke," said one City dealer.

But other speculated that Cadbury would want to concentrate on global confectionary, not snacks and frozen foods.

Difficult times

The talks follow a difficult time for United Biscuits, which made a loss in the last half year of £52m due to restructuring costs.

UB has been planning to sell off its frozen and chilled food business, including the Linda McCartney brand, in order to concentrate on its more profitable biscuits and snacks.

It has also placed its seafood business, Young's, in a joint venture with Legal & General's Bluecrest.

Earlier, it sold off its US Keebler biscuit operations.

United Biscuits' brands include Penguin, McVities, MCoys crisps and HulaHoops. It has 23,000 employees and worldwide sales of £1.6bn, primarily in Europe and the UK.