Moody's has slashed Ireland's sovereign debt rating by two notches, to BAA3 from BAA1, on its weak economic growth prospects.
Moody's says it could cut its ratings of 19 UK banks to reflect the lower chance of a future government bail-out.
Moody's has downgraded Portugal's credit rating for the second time in less than a month and has warned it could fall further.
Moody's says it has seen signs of improvement and increased profitability in the hedge fund sector this year following strong performance in 2010.
Moody's has downgraded Portugal's government debt two more notches because of 'subdued' growth prospects.
Japan's credit rating has been cut to ‘negative' by Moody's on debt level concerns.
Investors expect Moody's to cut its Aaa credit rating on Spanish debt by up to two levels after a three-month review it announced in June ends tomorrow.
The UK has maintained its AAA credit rating largely thanks to the austerity measures of the coalition government, although it remains vulnerable over the long term.