U.S., Britain, U.N. wary of South Sudan ceasefire announcement

South Sudan's President Salva Kiir delivers a speech during the launch of the National Dialogue committee in Juba, South Sudan May 22, 2017. REUTERS/Jok Solomun

UNITED NATIONS (Reuters) - The United States, Britain and the United Nations were sceptical on Wednesday of South Sudan President Salva Kiir's declaration of a unilateral ceasefire, noting that it coincides with the start of the rainy season that traditionally lessens fighting.

Kiir also said on Monday he would release political prisoners, but with no sign of a political deal with rebels it was not clear whether a ceasefire would take hold.