The Intergovernmental Authority on Development (Igad) has said it is up to the South Sudan government to decide whether Dr Riek Machar should be reinstated as the country’s first vice president.

That decision would be “naturally accommodated by Igad,” Sharon Kuku, a spokeswoman for the eight-nation grouping of East African states, said.

Ms Kuku noted that Taban Deng Gai, appointed by President Salva Kiir as Dr Machar’s replacement, had pledged at Igad’s August 5 Heads of States Summit to abide by the South Sudan government’s decision on the first vice presidency.

“Igad did not stop Gen Deng from attending the Summit nor speaking for the South Sudan government,” Ms Kuku pointed out.

The comment by Igad follows the group’s call on August 5 for Dr Machar to be reinstalled as first vice president. His removal was not consistent with the terms of last year’s peace agreement between South Sudan’s warring parties, Igad said three weeks ago.

In the interim, however, the United States had expressed its acceptance of Dr Machar’s replacement by Mr Deng.

Secretary of State John Kerry said in Nairobi on August 22 that “it’s quite clear that legally, under the agreement, there is allowance for the replacement, in a transition of personnel, and that has been effected with the appointment of a new vice president.”

The US position was later reaffirmed by State Department spokeswoman Elizabeth Trudeau.

READ: Envoy tells off Igad after Kerry’s remarks on Juba leadership changes

A faction of the armed opposition declared last month that it had chosen Mr Deng to replace Dr Machar, who was then in hiding inside South Sudan following bloody clashes in Juba.

South Sudan President Salva Kiir subsequently named Mr Deng as first vice president.

Dr Machar’s followers charged that the moves violated last year’s peace agreement and vowed to oppose Mr Deng’s appointment.

READ: President Kiir moves to isolate sacked deputy in Juba peace deal

State Department spokeswoman Trudeau on Thursday repeated US calls for an end to armed conflict in South Sudan.

“We do expect the transitional government and all parties, including all leaders of the opposition in South Sudan, to take every step possible to avoid fighting and to reach a peaceful resolution of their differences,” she said adding that the way forward is peaceful implementation of the agreement.