According to the Financial Times, US private equity firms Advent International and One Equity Partners have both submitted final offers for a 60% stake in the business in a deal that could be worth up to €600m (£527m).

It has been speculated that the proceeds from the sale of the smart card business, which contributed more than 70% of Oberthur's €712m turnover last year, could be used to finance a renewed bid for De La Rue, which successfully resisted an attempted takeover by its French rival in January.

At the time De La Rue's board refused to recommend Oberthur's increased 935p-per-share takeover bid, because it "significantly undervalued the company". A number of major shareholders were reportedly holding out for a bid in excess of £10-per-share.

Oberthur eventually withdrew its interest after a "put up or shut up" order by the London Stock Exchange (LSE) Takeover Panel and the following rejection of its final offer; however, City analysts raised doubts at the time over Oberthur's ability to fund its takeover attempts.

Chris Dyett, analyst at Investec told the Financial Times: "When they approached the De La Rue board previously, people were a bit unsure of where the funding was coming from. With the sale of these assets, that clearly gives them more firepower."

Oberthur maintained that it had no renewed interest in acquiring its rival when it appointed former De La Rue chief executive James Hussey as an advisor to its chairman in June. Hussey was the highest profile departure from De La Rue when he resigned following the crisis at the company's banknote paper mill in Overton in August 2010.