Sudanese Foreign Minister Mariam al-Sadiq al-Mahdi ruled out military action to stop Ethiopia filling its controversial Blue Nile mega dam, during a visit to Qatar Thursday.
Downstream neighbours Egypt and Sudan view the dam as a threat because of their dependence on Nile waters, while Ethiopia considers it essential for its electrification and development.
"There is no room to talk about the military option. We are now talking about political options," al-Mahdi told reporters in Doha.
The Grand Ethiopian Renaissance Dam has been a source of tension in the Nile River basin ever since Addis Ababa broke ground on it in 2011.
The comments come a day after Ethiopia said it would press on with filling the GERD dam, sparking warnings from Sudan and Egypt.
"There will be a significant mobilisation of global opinion -- and most importantly African opinion, especially in the neighbouring countries and Nile Basin countries -- to prevent Ethiopia from moving ahead with destabilising the security of its significant neighbours, Egypt and Sudan," she added.
Ethiopia says the power produced by the huge hydro-electric project will be vital to meet the development needs of its 110 million people.
Egypt and Sudan had wanted an agreement on the dam's operations to be reached before reservoir filling began last year.
Sudan's irrigation minister warned Wednesday that his country stood ready to harden its stance in the dispute.
"For Sudan, all options are possible, including returning (the matter) to the UN Security Council (UNSC) and hardening policy... (if) Ethiopia embarks on a second filling (of the dam) without agreement," Yasser Abbas told reporters.
On Thursday, Sudan's head of state Abdel Fattah al-Burhan, also in Doha, said he would "request all assistance" to reach an agreement.