Standard & Poor's joined Fitch in downgrading New Zealand's credit rating one notch, citing high external debts and the rebuilding cost after the Christchurch earthquake. S&P cut New Zealand's long-term foreign currency rating to "AA" from AA+" and it long-term local currency rating to "AA+" from "AAA". Friday's downgrade "follows our assessment of the likelihood that New Zealand's external position will deteriorate further at a time when the country's fiscal settings have been weakened by earthquake-related spending pressures and fiscal stimulus to support growth," it said in a statement.