Italian-based investment company Exor, controlled by the Agnelli family, said Monday it had struck a $6.9 billion (6.3 billion euro) deal to buy reinsurer PartnerRe.

Exor, already the largest shareholder of PartnerRe, said it had "signed a definitive merger agreement to acquire all of the outstanding common shares of PartnerRe for $137.50 per share in cash plus a $3.00 per share special dividend... valuing PartnerRe at approximately $6.9 billion."

"Today's agreement is very positive for PartnerRe and Exor. Under our stable and committed ownership, PartnerRe will continue to develop as a leading independent global reinsurer," said John Elkann, Exor's chairman and CEO.

An Exor statement said the agreement includes a six-week "go-shop" period during which PartnerRe can solicit and evaluate any competing offers.

PartnerRe said the deal meant it would end its separate agreement with Axis Capital and pay a $315 million termination fee.

The global firm's headquarters will be maintained in Bermuda, with a strategic presence on five continents, it said.