South Korea and the United States on Friday wrapped up their second round of talks on revising a nuclear cooperation agreement set to expire in March 2014.

Robert Einhorn, the U.S. State Department's special adviser for nonproliferation and arms control, met for a second straight day with his South Korean counterpart Cho Hyun, former deputy foreign minister for multilateral and global affairs.

The two sides discussed the basic framework for the new pact, as well as ways to enhance industrial and commercial cooperation in the nuclear power sector, the Yonhap News Agency reported.

The two also reportedly exchanged views on joint research on pyroprocessing, a technology for reprocessing spent nuclear fuel.

"The overall atmosphere of the talks was not bad," said an official at the Ministry of Foreign Affairs and Trade in Seoul quoted by Yonhap. "Both South Korea and the U.S. agree that cooperation is necessary in the nuclear power sector."

The two sides are planning to hold a third round of talks in the first half of the year, Yonhap said.

The nuclear agreement pact, signed in 1974, prohibits South Korea from reprocessing spent nuclear fuel. Seoul has demanded to revise the agreement as its storage facilities for spent fuel from nuclear power plants in the country are expected to reach capacity in 2016.

Seoul proposed pyroprocessing technology, considered to be less conducive to proliferation, as a solution, and at the first round of talks held in October last year the two sides agreed to conduct joint research into the technology.