Iranian negotiators arrived in Vienna on Tuesday for a new round of negotiations with world powers over a potential agreement on its nuclear program.

TEHRAN, May 12 (Xinhua) -- Iran hopes to reach a nuclear agreement with world powers before the end of June although some difficulties and obstacles remain, a senior negotiator said on Tuesday.

Iran and the P5+1 group are trying to reach a comprehensive agreement before the end of June, based on understanding agreed in early April.

"We are very much hopeful to reach the agreement even before the deadline is due," the official IRNA news agency quoted Iranian negotiator Abbas Araqchi as saying in Vienna.

However, many factors, both inside and outside the negotiation room, can hinder progress on the agreement, Araqchi said.

Araqchi said on Tuesday that senior Iranian negotiators will also hold separate meetings with top officials of the P5+1 group during this round of talks.

Araqchi and EU political director Helga Schmid are scheduled to meet on Tuesday. Expert-level meeting will also be held on the same day to work out details of the potential deal, according to state IRIB TV.

On May 15, deputy foreign ministers of the P5+1 group, namely Britain, China, France, Russia, the United States, plus Germany, will join the meeting, according to the report.