(Reuters) - Moody s Investors Service said on Tuesday that Puerto Rico and the U.S. Virgin Islands will face new challenges to credit quality and finances after the U.S. territories were battered by hurricanes Irma and Maria. Both territories will be heavily reliant on relief from the U.S. federal government, as they were hit by storms at a time when they were already suffering financial distress, Moody s said. Puerto Rico is undergoing a debt restructuring under federal oversight and the U.S. Virgin Islands has extremely weak liquidity. Moody s Analytics  preliminary estimate of Maria s total cost to Puerto Rico, including lost output, is $45 billion to $95 billion, representing about 65-135 percent of the territory s gross national product. 