An increase in New Zealand's government debt ratios will not push Moody's Investors Service to cut the country's AAA rating for NZ dollar debt.The ratings agency is projecting the debt/GDP ratio to peak at 55.5 per cent in 2014, up from about 41.3 per cent in 2010. But even at that level, it considers the ratio strong enough to justify a AAA rating.Moody's is comforted by the strength of the banking system, due mainly to the strength of the large New Zealand banks' Australian parentage.The contingent liability to the government's balance sheet from the banking system is small, said Moody's. It noted that potential risks to offshore funding as a result of the global financial crisis eventuated only for a brief period.Moody's rating view is in line with Standard & Poor's AAA rating with stable outlook on domestic debt, while Fitch has a negative outlook on the AAA domestic rating.The Moody's report made no specific mention of New Zealand's foreign currency rating. In November, S&P put the AA+ rating on a negative outlook citing the nation's level of offshore debt as the primary concern. Fitch also has a negative outlook on the foreign currency rating.