De La Rue announced this morning (24 January) that it had received an oral indication from Oberthur over the weekend that it was prepared to increase its indicative proposal from 905p to 935p per share.
Nicholas Brookes, chairman of De La Rue, said: "The board has carefully considered Oberthur's revised proposal and believes that it continues to significantly undervalue the company and its prospects. The board therefore unanimously rejected this latest approach.
"With the recent appointment of Tim Cobbold to lead a restructured and strengthened management team, the board is confident that De La Rue has a promising future as an independent company."
Cobbold, who took up the vacant chief executive role at the beginning of the year, added: "My first few weeks have confirmed my view that De La Rue is a high quality business with substantial potential in growing markets.
"There are, of course, opporunities for improvement, building on changes already made, but shareholders should be in no doubt of my absolute commitment to realise De La Rue's potential and deliver significant value."
According to the Financial Times, Oberthur has reached a £400m financing agreement with Bain Capital to help fund its bid for the world's largest banknote printer.
While the finance, which is understood to be in the form of a convertible bond, could theoretically pave the way for Oberthur to realise its ambitions, Bain is reportedly unwilling to involve itself in a hostile bid.
With De La Rue so far resolute in its resistance to Oberthur's advances and the 7 February offer deadline imposed by the Takeover Panel fast approaching, it seems unlikely that a deal will go ahead unless Oberthur is able to significantly raise its offer.
A revised offer from Oberthur is deemed unlikely until De La Rue issues its next trading statement, which is expected early this week.