AIG also said that Chartis has entered a one-year, $US1.3 billion ($A1.3 billion) letter of credit facility. There are 36 banks participating in the facilities. The agreement builds momentum for AIG, which earlier this month raised $US2 billion ($A2.0 billion) selling senior unsecured notes and established a $US500 million ($A498.93 million) contingent liquidity facility.