(Reuters) - Mitsui Sumitomo Insurance [MITSID.UL] said it had agreed to buy British insurer Amlin Plc (>> Amlin plc) for 670 pence per share in cash.

The deal with Mitsui Sumitomo Insurance, a wholly-owned subsidiary of MS&AD Insurance Group Holdings (>> Ms&Ad Insurance Group Holding Inc), values Amlin at about 3.46 billion pounds ($5.31 billion).

The deal is at a premium of about 36 percent over Amlin's closing price of 492.5 pence on Sept. 7.

(Reporting by Aashika Jain in Bengaluru; Editing by Anupama Dwivedi)

Stocks treated in this article : Amlin plc, Ms&Ad Insurance Group Holding Inc