NEW YORK (Reuters) - Wilbur Ross agreed to buy up to $1 billion in shares of bond insurer Assured Guaranty Ltd (AGO.N: Quote, Profile, Research), the company said on Friday, giving the billionaire investor a key foothold in the struggling market.

Under the agreement, WL Ross & Co LLC, the private equity firm founded by Ross, will purchase $250 million of common shares of Assured and provide a commitment to purchase up to $750 million of additional common shares at the option of the company.

http://www.reuters.com/article/ousiv/idUSN2912684920080229