Former M&S CEO Sir Stuart Rose resurfaced as chairman of Ocado this week as rumours circulated that M&S had revived its interest in buying the online grocer.

Speculation that M&S was once again considering a bid sent Ocado shares soaring 9% on Monday, and after the appointment was announced on Tuesday they gained another 6%, closing at 101p.

When he was CEO of M&S, Sir Stuart held takeover talks with Ocado a year before it floated in 2010, but they broke down.

The appointment of Sir Stuart, who takes over from former BBC chairman Lord Grade as Ocado chairman in March, could now pave the way for a deal to be resurrected, said analysts.

“It should add to the bid chatter that has surrounded the shares in recent months,” said Panmure Gordon analyst Philip Dorgan.

However, a deal was unlikely to happen any time soon, said Exane analyst John Kershaw. “If Ocado was about to be sold then Grade would have wanted to oversee that,” he said, adding that Ocado’s supply contract with Waitrose and the small basket sizes at M&S were major impediments to a sale.

Sir Stuart’s appointment was hailed as a major coup for Ocado as it prepares to open a second major warehouse in Dordon, Warwickshire.

“He’s a retailer whereas Michael Grade was an entertainer,” said Kershaw. “He’s well connected and he has experience competing with the big grocers.”

Ocado CEO Tim Steiner declined to comment on the takeover speculation, but said he was looking forward to benefiting from Sir Stuart’s “extensive retail experience and counsel”.

Sir Stuart said: “I believe Ocado’s model and high standards of customer service will see it emerge as a powerful online player.”