By Aaron Maasho
ADDIS ABABA Aug 7 (Reuters) - Mediators in South Sudan's troubled peace talks urged the government on Friday to let a prominent opposition figure join the negotiations, after police in the capital Juba blocked him from travelling.
Lam Akol, a vocal critic of President Salva Kiir, said on Wednesday he was barred from boarding a plane bound for the Ethiopia, where talks resumed this week, despite an invitation from the IGAD East African bloc.
"We call on the Government of South Sudan to immediately allow these and all invited representatives to travel and participate fully," IGAD, the United States, Britain, Norway, and other partners in the talks said in a joint statement.
Government officials in Juba have said they were not told Akol's political party had been invited to take part.
South Sudan descended into chaos in late 2013 following months of political bickering between Kiir and his former deputy Riek Machar. Fighting broke our, often pitting Kiir's Dinka people against Machar's Nuer group.
Akol is a Shilluk - an ethnic group whose members say they have been sidelined by both the Dinka and the Nuer.
The rival factions resumed negotiations on Thursday amid mounting international pressure and threat of further sanctions if an August 17 deadline is not met with a peace deal. Previous rounds had failed to break the deadlock with both sides violating ceasefire agreements.
Akol, a foreign minister of South Sudan when it was a semi-autonomous region before independence from Sudan in 2011, formed his SPLM-DC party after breaking away from the ruling SPLM.
He criticised the scrapping of elections that were due in June and opposed the extension of Kiir's term in office by three years. (Editing by Edith Honan and Andrew Heavens)
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