U.S. President Barack Obama has renewed American economic sanctions on Burma for another year, saying the large-scale repression of the democratic opposition in that country has not been resolved.

The move came late Monday as the State Department and rights groups renewed calls for the release of all 2,200 political prisoners in Burma. Human Rights Watch heaped scorn on the Burmese government’s announcement earlier Monday of a limited clemency program, calling it a “pathetic response” to demands for increased political freedom.

The clemency program, proclaimed by President Thein Sein, commutes death sentences to life imprisonment and reduces other jail terms by one year. It was not clear whether political prisoners will be included.

In his statement renewing U.S. sanctions on Burma, Mr. Obama said Burma’s continued repression of opposition parties poses an “unusual and extraordinary threat” to the national security of the United States. The language was nearly identical to that used in previous renewal statements.

Nyan Win, who is a spokesman for pro-democracy opposition leader Aung San Suu Kyi, said the one-year reduction in prison terms will not offer much benefit to political prisoners, most of whom are serving long sentences.

Human Rights Watch called the clemency program a “slap in the face” of a senior United Nations envoy who had just called for the release of all political prisoners in Burma.

Vijay Nambiar, the chief of staff to U.N. Secretary-General Ban Ki-moon, made the call at the end of a visit to Burma last week.