Afghan President Hamid Karzai and a high-ranking delegation departed Kabul on Sunday to meet with Iranian officials, including Iranian President Hassan Rouhani.

Karzai is visiting Iran to negotiate with Iranian officials on bilateral relations between Tehran and Kabul, the Presidential Palace said in a statement.

Karzai will meet his Iranian counterpart Hassan Rouhani today in Tehran, the statement added.

Karzai’s visit to Iran took place while the United States Secretary of Defense Chuck Hagel is visiting U.S forces in Afghanistan.

Hagel visited with American forces in Afghanistan on Saturday. The visit comes as Karzai refuses to sign the Bilateral Security Agreement (BSA), despite mounting pressure from Washington and Afghan officials.

Hagel’s unannounced visit lands him in the center of the chaos that has surrounded BSA negotiations in recent weeks, but he has no plans to meet with Karzai and may have little impact on the matter during his stopover.

Previous trips by U.S. National Security Advisor Susan Rice and Secretary of State John Kerry proved fruitless in resolving the remaining dispute between Karzai and the White House over the timeline and conditions for the finalization of the BSA.

Karzai last time visit Iran during Hassan Rouhani’s swearing-in ceremony on Aug. 4, 2013.

The visit comes after Iranian Deputy Foreign Minister for Asia and Pacific Affairs Ebrahim Rahimpour recently once again raised his country’s opposition to signing the security pact between Kabul and Washington.

“Iran, as a friend of Afghanistan, declared its opposition to signing the BSA to Afghan officials, because signing and implementing this agreement will damage the Afghanistan government and nation’s interests over the long term,” Rahimpour said.

“We advise Afghan officials to not sign the BSA in the current situation,” Rahimpour added.

At the same time in response to Iranian official’s comments, Afghan Foreign Ministry called the BSA his country’s right.

“As an independent country with proper understanding of its national interests, Afghanistan makes its own decisions to adjust its relations with the world and Afghanistan does not need approval in this regard,” Ershad Ahmadi, Deputy Foreign Minister for Political Affairs told.