Zurich Insurance Group AG is raising financing ahead of a possible takeover offer for RSA Insurance Group that could come as early as next week, according to people familiar with the matter.

The Swiss insurer is talking to banks about raising more than $4 billion, said two of the people, who asked not to be identified because the information is private. Zurich Insurance hasn’t made a final decision and is still discussing options with adviser Morgan Stanley, the people said.

Earlier this week, Zurich said it was considering a bid and any offer for RSA would probably be in cash. London-based RSA has a market value of 5.2 billion pounds ($8.2 billion), reflecting gains following the reports of takeover interest.

Analysts at Panmure Gordon & Co. estimated the British insurer would fetch about 5.7 billion pounds. Zurich, a Swiss insurer, reiterated in May that it would redeploy $3 billion in excess capital by the end of 2016.

While Zurich is talking to more than one bank about the financing, it could also opt to raise the funding solely through Morgan Stanley, one of the people said.

Representatives for Zurich and RSA, which are both scheduled to report earnings on Aug. 6, declined to comment. A spokesman for Morgan Stanley declined to comment.

Allianz, Axa

European insurers, crimped by tighter regulation and the debt crisis, may be turning to mergers for relief. Analysts have said Allianz SE, Europe’s biggest insurer, and France’s Axa SA may also bid for RSA, whose shares have trailed peers in the past year.

A deal would be Zurich’s largest since 2000 and let Chief Executive Officer Martin Senn expand in the U.K. and Latin America. It would also bring access to RSA’s profitable Scandinavian and Canadian units. The company has a market value of 44 billion Swiss francs ($46 billion).

For RSA, a takeover would cap a tumultuous period, including an accounting scandal in Ireland in 2013, Simon Lee’s departure as CEO, a stock sale and a spate of asset disposals to shore up the balance sheet. Stephen Hester, the former CEO of Royal Bank of Scotland Group Plc, took the reins at RSA last year.

–With assistance from Jeffrey Vögeli in Zurich and Sarah Jones in London.