Italian investment firm Exor will carry on meetings with target takeover PartnerRe’s analysts and investors as part of its $6.8 billion bid to take over the firm.

And Exor accused PartnerRe — which is backing a merger with Axis Capital over Exor’s offer — of an “irresponsible campaign of intentionally and inappropriately misleading its shareholders”.

Exor said: “The more the PartnerRe board misleads its shareholders on the merits of the Exor offer, the clearer it is that the inferior Axis transaction is short on substance and long on execution and integration risks for its shareholders, employees and clients.”

The salvo was the latest in a long-running battle for control of PartnerRe.

Exor raised its original $6.4 billion bid for the firm in May to the equivalent of $137.50 a share.

The all-cash deal went up against the all-share merger proposal and Exor said it intended to keep PartnerRe as a stand-alone company and retain existing management and staff.

The PartnerRe/Axis deal would create the world’s fifth largest reinsurer and both companies have said they would make $200 million in savings — with some of cash coming from redundancies among the combined Bermuda-based staff of 130.

The Exor statement yesterday said its bid would be better for ordinary shareholders and preferred shareholders — the latter of which amount to 40 per cent of the shareholder vote.

It added that its bid would mean no execution risk and retain the same regulatory covenant as the Axis offer.

Exor added it had invested $600 million in PartnerRe, becoming the largest single shareholder and was “more incentivised” than any other stakeholder to close a deal with the target by the end of the year.

And the Italian firm, controlled by the billionaire Agnelli family, which has large stakes in carmaker Fiat Chrysler and Italian football club Juventus among its holdings, said there would be no integration risk with its offer and it would give PartnerRe the strength of “a larger, stronger group” with assets of around $15 billion.

But PartnerRe hit back and said that Exor’s claim that ratings agency Standard & Poor’s had not taken a view on its ratings in relation to sale to Exor.

A spokesman for PartnerRe added: “Standard & Poor’s has provided a view on Exor’s ratings in relation to a potential acquisition of PartnerRe — it has revised its outlook on Exor’s ratings to negative.”

It added that the ratings agency had affirmed PartnerRe’s and Axis’ ratings as stable in the event of a merger.