The next round of talks between Iran and the West over its nuclear program will take place next week, the State Department said on Monday, according to Reuters.

The announcement said that Secretary of State John Kerry will travel to Lausanne on March 15 for the talks.

Kerry will meet with Iranian Foreign Minister Mohammad Javad Zarif as part of the ongoing negotiations, according to the State Department.

Iran and the six world powers are trying to turn an interim 2013 deal into a permanent agreement.

Under the interim deal, Iran committed to limit its uranium enrichment to five percent and is gradually winning access to $4.2 billion of its oil revenues frozen abroad and some other sanctions relief.

Talks to reach a permanent deal have continuously stalled and two deadlines for a final deal have been missed, with a third one looming on July 1 and an initial deal needing to be worked out by March 31.

Zarif suggested last week that a 10-year moratorium on some aspects of his country’s nuclear program might be acceptable to Tehran, after President Barack Obama had said that Iran must commit to a verifiable freeze of at least 10 years on sensitive nuclear activity for a landmark atomic deal to be reached between Tehran and six world powers.

“It depends on how you define it,” Zarif said when asked about Obama’s comments. “If we have an agreement, we are prepared to accept certain limitations for a certain period of time but I’m not prepared to negotiate on the air.”