LONDON - U.S. sanctions announced on Thursday on newly-issued Russian government debt could see the bonds excluded from JPMorgan's influential emerging market local-currency GBI-EM investment index, the bank said.

"Economic sanctions which impact the replicability of the J.P. Morgan fixed income indices will result in an Index Watch (observation period) followed by potential rebalance actions such as exclusion of the sanctioned bonds/issuers from the benchmark," JPMorgan said.