Zurich Insurance abandoned its proposed £5.6bn (€7.75bn) bid for Britain's RSA yesterday, after forecasting a £129m third-quarter loss largely due to the devastating explosions at the Chinese port of Tianjin.
A day before a bid deadline under British takeover rules, Zurich said it would conduct a review to improve the performance of its general insurance business, instead of taking over its London-listed rival.
The announcement sent RSA shares down by as much 23pc.
RSA, which is pursuing a turnaround strategy under former Royal Bank of Scotland boss Stephen Hester, said Zurich had found nothing untoward in its "due diligence" checks on its books that would have thwarted a deal on the 550 pence per share terms proposed on August 25.
RSA, which operates the 123.ie insurance brand here, also said its July and August trading had been positive, but its shares were trading at 404p in early trading, 8pc below their closing price the day before Zurich said it was weighing a bid.
Zurich, whose shares were down 1.6pc at 257.8 francs in early trading yesterday, announced aggregate losses of around $275m from the massive explosions at a container storage station in Tianjin last month.
It said the final cost was uncertain but it did not expect a significant rise in claims. The Swiss insurer also said recently completed reserve reviews indicated a likely negative impact of around $300m in the third quarter for US auto liability and other lines of business.
"Given the deterioration in profitability ... General Insurance CEO Kristof Terryn is conducting an in-depth review of the business," Zurich said in a statement.
A spokeswoman for the company said it remained on the lookout for acquisitions and a sale of its general insurance business was not an option, as a large part of those operations remained profitable.
The company is likely to hit the lower end of its mid-term targets for a 12pc to 14pc after-tax return on equity from operating profit for 2014-2016, the spokeswoman added.
RSA, which swung into profit last year following losses in 2013 and posted above-forecast results in the first half, had stressed it had not put itself up for sale and was confident on its prospects.
However the company had become a takeover target after a fall in its share price on the back of 2013 losses that followed series of weather-related claims and the discovery of a €274m hole in the accounts of its Irish unit.
Tougher regulation and hefty competition in the insurance sector, including from non-traditional providers, have encouraged a number of insurance tie-ups.
But analysts were doubtful other bidders would come forward to buy RSA, after European rivals Allianz and AXA, which like Zurich offer both life and general insurance, had indicated they were not interested.
RSA shareholders had welcomed the proposed offer, but some Zurich investors had said they would prefer the cash-rich insurer to give money back.
Activist investor Cevian Capital, RSA's largest shareholder with a 13pc stake, declined to comment.