U.S. Secretary of State John Kerry has boosted expectations here for an early revision of the nuclear accord between Seoul and Washington by saying that the thorny issue could be settled before early next month.

After talks with South Korean Foreign Minister Yun Byung-se in Washington on Tuesday, Kerry said in a news conference that he was “very hopeful that this can be resolved before the visit of President Park Geun-hye.”

Park is scheduled to visit Washington in early May for a summit with U.S. President Barack Obama.

Noting the close cooperation that the two countries have had in nuclear energy for decades, Kerry said that “we are committed to finding a workable, expeditious way forward” to ensure that the partnership “will continue in an agreed-upon fashion.”

Kerry’s optimistic tone has eased concern here that the two countries might not be able to reach a new deal on nuclear energy cooperation in time.

The existing nuclear agreement between the two allies was signed in 1974 and is to expire next March. A new deal needs to be hammered out before June in consideration of the time needed to win approval from the U.S. Congress.

To revise the outdated pact, the two countries started negotiations in 2010 and have since held five rounds of talks. But they have failed to make much progress. Following the foreign ministers’ meeting, the two sides are to begin their sixth round of talks soon.

The main sticking point concerns uranium enrichment and reprocessing of spent fuel. Under the current pact, Seoul is allowed neither to enrich uranium nor reprocess spent fuel.

As a result, Seoul has been importing enriched uranium from the U.S. and Europe to fabricate the fuel domestically. Now, it wants Washington to allow it to enrich uranium to a low level to attain self-sufficiency in nuclear fuel supply.

But Washington has thus far rejected Seoul’s request on the grounds that uranium enrichment could lead to nuclear weapons development. For the same reason, it is also opposed to allowing Seoul to reprocess spent fuel.

Yet Seoul faces an imminent spent-fuel management crisis. The nation’s 23 nuclear power plants produce about 700 tons of spent fuel a year. Currently spent fuel rods are temporarily stored in spent fuel pools at reactor sites.

But these pools are already almost full with more than 10,000 tons of spent fuel. They are expected to reach capacity soon, starting with the one at the Gori power plant in 2016.

To avert the imminent crisis, the government has sought to build an interim storage facility. But it has not been able to choose a suitable site in the face of the “not-in-my-backyard” syndrome among residents.

Seoul has another strong case for seeking the right to enrich uranium and reprocess spent fuel. In recent years, the nation has emerged as a major exporter of nuclear technology. But the nuclear accord with the U.S. puts it at a disadvantage vis-a-vis its rivals.

Seoul’s competitors can provide their customers with the full range of services, ranging from reactor construction to supply of nuclear fuel and disposal of spent fuel. But the nation cannot offer the full nuclear fuel cycle services, which undermines its competitiveness.

Against this backdrop, Kerry’s positive comments led some to speculate that Seoul and Washington might have narrowed their differences considerably in the process of preparing for the foreign ministers’ meeting.

Minister Yun fueled the speculation by saying that “the devil is in the details.” His comment suggests the two sides have agreed on the framework of the new deal, although its details still remain to be sorted out.

Yet Seoul officials played down Kerry’s remarks, describing them as diplomatic rhetoric. They cautioned against interpreting his commitment to an early resolution of the impasse as an indication of Washington’s willingness to accept Seoul’s demands.

According to news reports, Washington is still maintaining its principle of not allowing any country that enters into a nuclear agreement with it to enrich uranium or reprocess spent fuel.

If that is true, Seoul needs to press its case in the upcoming round of talks, based upon its track record of abiding by international obligations and its firm commitment to nuclear nonproliferation, which was best demonstrated by Seoul’s hosting of the Nuclear Security Summit last year.

As Yun told Kerry, the accord should be rewritten “in a mutually beneficial, timely and forward-looking manner.”