AXA may be planning another UK acquisition following its merger with Guardian last May, according to a leading analyst.

Speculation has been prompted by Axa moving to buy out the minority shareholding in the subsidiary company for its UK operations, Sun Life and Provincial Holdings.

But a spokeswoman for Axa, in Paris, said the insurer could not comment.

Axa has told the London Stock Exchange that it has started talks to acquire the minority 43.7% shareholding in SLPH, the holding company for Axa Sun Life, Axa Insurance and PPP healthcare.

A spokesman for SLPH confirmed the move, saying Axa was in discussions with SLPH's non-executive directors who are representing the interests of SLPH's minority shareholders in the preliminary negotiations.

The Prudential is the next largest shareholder after Axa with 5.9% of SLPH, Axa has 56.3%. Its shareholding in SLPH was reduced from 72% after its merger with Guardian last May.

Mark Williamson, an insurance market expert with analysts RZH, said the minority 43.7% stake in SLPH could cost Axa up to £2bn to acquire if SLPH shares are valued at 500p.

Their price fell back to 440p on Tuesday morning after opening at 525p when the market closed on Monday. He believes Axa's decision to buy-out SLPH's minority shareholders could be a planned move prior to Axa launching another takeover bid.

Williamson said: "This is an opportunistic move on Axa's part. They see real value in the SLPH minority shareholding and acquiring this would add value to their own shareholding."

Furthermore he added: "If there was further consolidation in the UK insurance market, Axa might be prepared to make another acquisition to retain their leading position."