Zurich made a proposal this morning (25 August) to purchase RSA's entire share capital in cash for 550p a share, which RSA's board said it could recommend subject to further negotiations.
In addition to 550p a share, the offer includes a 3.5 pence interim dividend per ordinary share to be paid to RSA's shareholders - a proposal announced by RSA at its first half results' announcement on 6 August.
RSA's board said it would be willing to recommend the offer to RSA's shareholders subject to "the satisfactory resolution of other terms of the offer".
The possible offer is conditional on due diligence.
The closing deadline for Zurich to make an offer without an extension according to the City Code on Takeovers and Mergers was 5pm today; however this deadline has now been extended to 22 September with the consent of RSA.
Zurich said the proposal is not an announcement of a firm intention of an offer and that there can be no certainty an offer will be made.
The offer would value RSA at around £5.6bn. RSA's shares closed at 495p yesterday (24 August).