U.S. President Barack Obama approved a civilian nuclear energy cooperation deal with South Korea on Thursday, saying it will promote the "common defense and security."
  

In April, the two countries initialed the revision to their 1974 nuclear cooperation pact after more than four years of negotiations to reconcile Seoul's demand for the right to reprocess spent nuclear fuel and enrich uranium with Washington's concerns about proliferation.
  

The new deal still bans Seoul from reprocessing and enrichment, but it opens the way for the Asian ally to begin research into a new technology for spent nuclear fuel recycling, known as "pyroprocessing," and to make low-level enriched uranium with U.S. consent.
  

"I have determined that the performance of the proposed agreement will promote, and will not constitute an unreasonable risk to, the common defense and security," Obama said in a memorandum for the secretary of state and the secretary of energy.
  

"I hereby approve the proposed agreement and authorize the secretary of state to arrange for its execution," he said.
  

South Korean President Park Geun-hye has already approved the agreement.
  

The two countries should now formally sign the deal before the it is sent to Congress for approval. No legislative approval is necessary in South Korea.
  

The two countries had planned to hold a signing ceremony next week during Park's visit to Washington, but the plan fell through as she postponed the trip due to the massive outbreak of Middle East Respiratory Syndrome in South Korea.
  

Once it is formally signed, Congress will review the agreement for 90 congressional days, which could take up to six months, and the pact will take effect if no opposition is raised during the review. (Yonhap)