TOKYO/ZURICH (Reuters) - Japan's SoftBank Group Corp is looking to buy a 25 percent stake in Swiss Re worth about $9.6 billion (£6.81 billion) as the firms' talks over a potential deal advance, Bloomberg reported.

The talks are centering on 100 to 105 Swiss francs a share, Bloomberg said, citing people with knowledge of the matter, adding that the terms of the potential deal were still fluid and that the companies could fail to reach an agreement.

SoftBank declined to comment on the report on Thursday.

A spokeswoman for Swiss Re reiterated that the reinsurer's board of directors was examining possible strategic and financial implications of a potential partnership with SoftBank, but insisted the company's capital situation was strong and it was not considering raising new capital.

"It is uncertain whether there will be an agreement, what the conditions and timing could be or what form a potential transaction could take," the spokeswoman said in an emailed statement.

Swiss Re's shares, which closed on Wednesday at 95.16 francs, were set to open 2.9 percent higher, according to pre-market indications by bank Julius Baer .

SoftBank's shares closed down 1.5 percent.

(Reporting by Makiko Yamazaki and Chang-Ran Kim in Tokyo and Silke Koltrowitz and Angelika Gruber in Zurich; Editing by Edwina Gibbs and Michael Shields)

Stocks treated in this article : SoftBank Group Corp, Swiss Re