Sudan, South Sudan must act on agreements: US envoy - Radio Netherlands

South Sudan and Sudan must act on agreements to open their border for trade and resume oil production for the sake of their people, the top US envoy to the former civil war foes said on Friday.

Princeton Lyman, US special envoy to the two eastern Africa nations, said that additional demands by Khartoum were "troubling" for the peace process, which aims to settle a raft of issues unresolved since the South won independence last year.

The September deals mediated by the African Union included setting up a demilitarised border buffer zone to cut support for insurgents in Sudan, and to allow a resumption of South Sudanese oil through northern pipelines for export.

But concern has grown that the agreements have not gone into effect after Sudan's President Omar al-Bashir and his South Sudanese counterpart Salva Kiir hailed them as ending conflict.

Khartoum’s demands for "additional assurances" for those deals is stalling a process that is "for the betterment of the people in both countries", Lyman told reporters in the South Sudanese capital of Juba.

"It’s not absolutely clear what kind of additional assurances would be more important or more effective than demilitarizing the border and setting up a joint monitoring of the border crossing points," he said.

Under a peace deal which ended a 1983-2005 civil war, South Sudan became independent last year, but the two countries fought along their undemarcated border in March and April.

Both countries accuse each other of backing rebels to destabilise their nation.

Demilitarisation of the border and joint border monitoring teams will provide "assurances that support is not travelling across those borders for either country," Lyman said.