Standard & Poor's has affirmed its 'AAA' ratings on US property & casualty insurer American International Group (AIG).

S&P also raised its ratings on several AIG entities to 'AAA' because of their core status within the AIG group.

Standard & Poor's credit analyst Grace Osborne said: "The ratings are based on AIG's well-diversified business position, track record of excellent operating performance and very strong levels of capital adequacy."

Looking to the future S&P said AIG's business mix is expected to become more skewed toward domestic lines.

The ratings agency added that its property & casualty business is expected to remain robust, in light of improved market conditions.