Sir Tom Hunter is expected to raise his stake in Dobbies to nearly 30 per cent after he continued to wage a tit-for-tat share buying campaign for the garden centre operator with Tesco.

Sir Tom disclosed yesterday that he had bought 90,000 more shares, taking his stake to 27.66 per cent a day after Tesco revealed it had raised its stake to 29.9 per cent the day before. It is understood that neither side can raise their stake in Dobbies above 29.9 per cent under Takeover Panel rules and so Tesco must now hope to gather the backing of independent investors in order to win control of the company.

The supermarket needs the support of investors representing 50.1 per cent in order to make its bid unconditional. Including the shares it now owns, Tesco has acceptances representing 34.4 per cent and investors have until August 19 to accept Tesco’s offer.

If it does not get sufficient support, Tesco cannot bid for another 12 months without special dispensation from the Takeover Panel. Sir Tom is not allowed to bid for six months, unless certain conditions are met.

Because Sir Tom owns more than 25 per cent of the company, Tesco will not be able to delist Dobbies even if it does gain control of more than 50 per cent of the company’s shares, but it will have the power to remove the dividend and to run the company. However, Sir Tom will be able to veto any plans for financial engineering, such as a sale and lease-back of Dobbies’ property portfolio.

Shares in Dobbies slid 25p to £14.75 yesterday as it appeared that most remaining investors were intending to accept Tesco’s offer.

James Barnes, chief executive of Dobbies, who has accepted Tesco’s bid, has written to independent investors urging them to accept the offer. He said that Sir Tom’s aim appeared to be just to derail Tesco’s bid. “If this deal went through that would not be favourable for him,” Mr Barnes said.

Sir Tom owns Dobbies biggest rival, Wyevale, as well as the Blooms garden centre and a stake in Flying Brands, which delivers flowers via mail order. The Scottish entrepreneur has said he wants to share in Tesco’s plans to develop Dobbies and is understood to have refused the supermarket’s attempts to offer him more cash.

Richard Ratner, an analyst at Seymour Pierce, said: “I don’t think he will make a bid. For a £40 million investment, he is protecting his other businesses. Nothing would suit him more than to have Tesco and him with 29.9 per cent each.”

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