The Bank of England's Prudential Regulation Authority has written to about 30 insurers to ask if they knew when changing temperatures or more frequent extreme weather disasters might start affecting the viability of their business model, the Financial Times reported on Monday.

The letter also asks if companies have considered the way climate change could affect their investment portfolios, the FT said.

"We have responded to the letter fully, we welcome the fact that we could do that," the Aviva spokeswoman said.

The Bank of England declined to comment.

The letter is thought to be part of a review by Britain's environment department of the impact of climate change across a range of industry sectors. The fact-finding mission started around a year ago and is due to be completed next year.

Insurance companies have at times been exposed to sharp losses in recent years from natural disasters such as hurricanes. Insurers are also aiming to improve the returns they make from investing their insurance premiums.

The issue has increasingly become a factor for global investors, some of whom are looking to low carbon investments as a way to benefit from attempts to counteract the adverse effects of climate change.

(Reporting By Carolyn Cohn in London, editing by David Evans)