UN Secretary-General Ban Ki-moon on Wednesday stressed Iran should gain the confidence of the international community over its disputed nuclear program.

During the meeting with Iran's foreign minister in Vienna, Ban said the onus remained on Iran to gain the confidence and trust of the international community.

Ban said he was encouraged that Iran and the six world major countries meet in Almaty, when discussing Iran's nuclear program with Iranian Foreign Minister Ali-Akbar Salehi in Vienna on Wednesday.

In addition, Salehi told reporters that he was optimistic an agreement could be reached in the negotiations between Iran and the six countries, namely France, Germany, the United States, China, Russia and Britain, which ended without a breakthrough but agreed to meet again.

Iranian chief nuclear negotiator Saeed Jalili expressed optimism Wednesday about the outcome of the two-day nuclear talks, saying that the world powers' attitude toward Iran's nuclear issue was "more realistic."

The two-day talks between Iran and the P5+1 powers concluded on Wednesday in Almaty, Kazakhstan.

Jalili said after the meeting that some of the West's offers, including the easing of sanctions "were more realistic comparing to what they had in the past."

In the talks, Iran urged that the steps to build confidence of both sides should be taken simultaneously and in a balanced way, so that Iran's nuclear rights could be preserved, he said.

An expert-level meeting was decided to be held in Istanbul, Turkey, on March 17 to 18, he said, adding that another high-ranking meeting will be held in Almaty, Kazakhstan, again on April 5.

He pointed out that continuation of the talks will be "a positive step" toward resolving the differences.

On Wednesday, world powers attending the new round of Iranian nuclear talks said that the meeting in Almaty had produced positive results. Endi