Talks between Iran and Western powers about ending the former's nuclear program in exchange for a lifting of economic sanctions could be extended for six more months if leaders from both sides cannot reach an agreement by July 20, Reuters reported, citing an Iranian official.

Delegates from six countries including the U.S., UK, France, Germany, Russia and China have met repeatedly with Iran over the past four months, when negotiations began, with the latest interaction happening Monday when American and Iranian officials met in Geneva. Negotiations had stalled last month after both sides accused the other of making unreasonable demands.

"We hope to reach a final agreement (by July 20) but, if this doesn't happen, then we have no choice but to extend the Geneva deal for six more months while we continue negotiations," Abbas Araqchi, Iran’s deputy foreign minister, said according to Reuters, which cited state news agency IRNA, adding: "It's still too early to judge whether an extension will be needed. This hope still exists that we will be able to reach a final agreement by the end of the six months on July 20."

While talks are set to resume Tuesday, concerns remain that, if left unresolved, the issue might trigger a conflict in the Middle East.

The U.S. State Department said Saturday that it will send Bill Burns, the deputy Secretary of State, and Wendy Sherman, a key negotiator, to meet a delegation led by Araqchi in Geneva, and that it hoped to make some headway in the negotiations.

"We don't have very much time left. We think we've made progress during some rounds but as we said coming out of the last one we hadn't seen enough made, we hadn't seen enough realism,” Marie Harf, the deputy spokesperson for the U.S. State Department said Monday, according to Reuters, adding: "Hopefully these discussions, like the other bilateral discussions people have, can help get us to the place we want to be."

France has also reportedly pushed for a quick conclusion to the talks and will be meeting officials representing Tehran on Wednesday during the Vienna negotiations, while Russia will meet Iran’s officials on Wednesday and Thursday, Reuters reported, citing state media.

"There are still gaps between Iran and the (six powers) in various issues and in order to bring our views closer, the other side must make tough decisions," Araqchi said, according to Reuters, adding: "The goal of these negotiations was to secure the Iranian nation's rights in the nuclear issue for peaceful purposes."