Volkswagen yesterday sparked the prospect of a bidding war for Rolls-Royce with the revelation it had tabled a 'concrete offer' for the British luxury car group. VW said terms of the offer were secret, but disclosed the bid had been made on Tuesday, ahead of what it said was a final deadline. The German car-maker's compatriot rival BMW said yesterday it had not yet made a bid for Rolls-Royce but refused to rule it out. 'There remains a healthy level of competition for Rolls,' a spokesman for Vickers, the British engineering group which owns Rolls, said. VW's bid is the first to be made since Vickers said it was looking for a buyer. Announcing last year's net profits had doubled to 1.361 billion deutschemarks (about HK$5.75 billion), VW chairman Ferdinand Piech said his offer was 'in line with what the selling party has offered.' Analysts have said the sale of Rolls-Royce could raise anything between GBP250 million (about HK$3.24 billion) to GBP400 million, depending on the level of interest. Despite its failure yet to show its hand, analysts said BMW was still the favourite to buy Rolls, given that BMW already supplies eight and 12 cylinder engines and other major components for Rolls and Bentley vehicles. Vickers was thought more likely to want to do a deal with BMW as it would be more 'in-house' than any other, although most analysts believed Vickers would accept only the best deal and that if it lost a bidding battle it would still have to honour its supply contracts. A successful takeover of Rolls-Royce by VW would go a significant way to achieving Mr Piech's ambitions to build a presence in the top-end of the prestige car market, where his company has yet to establish a prominent foothold. Prior to yesterday's announcement Mr Piech had said it would make sense for VW to position a brand just above Audi, which has successfully built a niche in the executive car market. News that a potential bidding war for the company could break out, sent Vickers' shares up almost 3 per cent to 232 pence. Daimler-Benz has ruled itself out of a bid, but some analysts suggested that some of the large US groups could become involved.