NEW YORK (Reuters) - American International Group Inc (AIG.N: Quote, Profile, Research) Chief Executive Martin Sullivan on Tuesday told investors that the insurance company's recent issue of equity and debt raised in the region of $20 billion, far more than initially expected.

Sullivan, speaking at an investor conference in London, said that the capital raising, announced after AIG reported a record $7.8 billion first-quarter loss, would give AIG the ability to invest in future growth, while at the same time position the company for further volatility in the credit markets.

AIG's quarterly loss was largely driven by write-downs of assets linked to subprime mortgage investments.

The company had initially planned to raise $12.5 billion.

(Reporting by Lilla Zuill; Editing by Steve Orlofsky)