A top European Union official might visit Tehran within days to hold talks aimed at restarting nuclear negotiations in Vienna, Bloomberg reported on Tuesday.

According to unnamed officials, EU deputy foreign policy chief Enrique Mora is expected to travel to Iran to try to pave the way for Tehran’s return to negotiations that were suspended in June. At the time Iran said its new president needed time to form a government, but after more than three months the Islamic Republic has still not given a firm date for its return.

The United States and Europe have warned that time is running out and they would not wait “forever” for Iran to rejoin the talks. It is not clear if Iran has been making new demands. Iran’s foreign minister last week signaled that his country wants the US to unfreeze its blocked funds, but Germany, one of the negotiating countries, said Tehran cannot make new demands.

"Iran cannot set any further conditions for resuming the talks," a German foreign ministry spokesman said.

Bloomberg said that a spokesman of the European Commission, Peter Stano declined to comment on news of Mora’s possible trip to Tehran.

It also drew attention to tightening energy supplies in the world and said that the fate of the talks is being closely watched by energy markets.