Just hours before the deadline to revise its offer, the Canadian firm said it would pay 235p per share for G4S – up from its previous offer of 190p.

It said the ‘final’ was an ‘attractive premium’ to where the shares were trading before it made its interest known in June, and urged investors to back it.

As part of the offer, Garda said it had also reached a deal with the G4S pensions trustees on a £770m funding package for its retirement scheme. And it slashed the level of shareholder acceptance it needs from 90pc to 50pc plus one share.

Garda has received acceptances from shareholders owning around 0.17pc of the company so far. In what has been a bitter takeover battle, Garda has accused G4S bosses of destroying the company’s value.

They in turn have claimed that Garda’s previous bids undervalued the business and that it would not be a suitable owner.

Yesterday, Garda boss Stephan Cretier said: ‘Shareholders have a simple choice: remain invested in a company which has consistently failed them and the wider community for so many years, or realise their investment in cash, at a significant and highly attractive premium.

‘There can be no better owner for G4S than Garda World. We urge shareholders to accept our final offer, doing so in the knowledge that G4S’s customers, employees, pension scheme members and the wider public will finally get the excellent service, invigorating working culture and safe pension benefits they deserve.’

G4S said it was examining the new bid. ‘In the meantime, shareholders are strongly advised to take absolutely no action in relation to the revised offer,’ it added.

It remains in talks with another suitor, rival Allied Universal, after it rejected a separate £3.25bn approach from that company last month.

Allied must make a formal offer by December 9 if it plans to do so.

Following the flurry of statements, G4S shares closed 7.4pc, or 17p, higher at 246p – suggesting investors believe Allied could come back with an even higher offer.

G4S shareholders have until December 16 to decide if they want to accept Garda’s final, higher offer.

Bosses at G4S said last month that they will start paying a dividend again and painted a bright future, claiming it can reach revenue growth of between 4pc and 6pc a year if it remains independent.

But it reported a £91m loss for 2019 after writing down the value of its cash handling business. It plans to cut more than 1,000 jobs, to cut costs.

Michael Hewson, analyst at CMC Markets, said: ‘G4S management has been pushing back for some time against Garda World.

‘However, with Allied Universal Security also lurking, shareholders are likely to find this new offer compelling, especially since the shares are up over 50pc since the initial September bid.’

© Daily Mail