G4S, one of the world's largest private security firm, last week rejected GardaWorld's 190 pence per share offer valuing the London-listed company at 2.97 billion pounds, calling it "unattractive and opportunistic".

GardaWorld said on Tuesday the offer was made "having assessed the many immediate and longer-term risks that are attached to the G4S business."

The firm offer, made at the end of September, followed an earlier offer last month for the same amount apiece, which was also rejected by G4S. The UK-based firm also turned down two prior proposals of 145 pence per share and 153 pence per share each.

Shares in London-listed G4S, which did not provide immediate comment, were up 1.3% at 203.7 pence by 1244 GMT. Since GardaWorld made its offer for G4S public on Sept. 14, G4S shares are up 39%.

Under Chief Executive Officer Ashley Almanza, who has led the group for the past seven years, G4S had rejected a 1.55 billion pound offer in 2013 from Charterhouse Capital Partners for its cash-handling business. (https://bit.ly/36A0IOC)

In February this year, it sold that unit, barring a few operations including the one in the UK, for 727 million pounds to U.S. peer Brinks Co. The retained UK cash operations have attached pension obligations.

"GardaWorld and BC Partners have a definitive plan to address G4S's pensions issue and take this massive burden off shareholders' shoulders," the private equity-backed Canadian company said in a statement.

(Reporting by Yadarisa Shabong in Bengaluru; Editing by Shailesh Kuber)