Six major powers have met in New York to discuss what further action to take against Iran for its failure to curb its nuclear program.
But the meeting of the so-called P5+1 group failed to make any decision on fresh sanctions, although an EU official who chaired the meeting said sanctions are "now on the agenda."
Officials from Britain, China, France, Russia, the United States and Germany met to discuss Iran's response to their offer in October to exchange uranium for nuclear fuel.
The meeting came after Iran ignored U.S. President Barack Obama's December 31, 2009, deadline to respond to the offer.
But the Russian representative at the meeting, Deputy Foreign Minister Sergei Ryabkov, said the session was "inconclusive in the sense that we didn't make any decisions right away."
Robert Cooper, a senior EU official who was the chairman of the meeting, also played down its significance. He said the session was "technical" in nature and that this was not a meeting at which it "was ever planned to make decisions."
"The conclusion that we reached in this meeting [is] that Iran has failed to follow up on the key understandings of the Geneva meeting by refusing further meetings to discuss the nuclear issue," Cooper said.
The background for the meeting in New York, Cooper said, was a previous meeting in October in Geneva which also included an Iranian delegation. That meeting was thought to provide an opportunity to seek a comprehensive long-term solution to the Iranian nuclear issue through dialogue and negotiation, but regrettably, Cooper said, it did not happen.
In addition to that, Cooper explained, the P5+1 were concerned by three related issues of Iranian non-compliance.
The first is that Iran has been secretly building an uranium enrichment facility near Qum with no credible civilian purpose, without notification to the International Atomic Energy Agency, or IAEA, and in violation of UN Security Council resolutions.
The second concern, Cooper explained, is Iran's lack of cooperation with the IAEA and the lack of clear response to the IAEA inquiry for clarification on specific aspects of its nuclear program.
The third concern is Tehran's refusal to accept the IAEA proposed agreement for the provision of nuclear fuel for its research reactor:
Cooper said that despite the lack of a concrete outcome, further sanctions were now on the big-power agenda and the six would be in contact again soon to continue the discussions.
"As a result we concluded the Iran's response was inadequate, that it had failed to take the opportunity that our ministers set out in September. The group remains united and underlines its unity, it remains committed to the two-track approach. That implies that we will continue to seek a negotiated solution but consideration of appropriate further measures has also began," Cooper said.
The U.S. representative at the meeting, the Under Secretary of State for Political Affairs William Burns, said the session was "useful."
U.S. Secretary of State Hillary Clinton has said the Obama administration thinks the best way to pressure Iran is to impose new sanctions aimed at the country's ruling elite.
But analysts say China and Russia are skeptical of new sanctions and the White House's aggressive approach.
China was represented at the talks by Kang Young, a counselor at China's mission to the UN and the lowest-level diplomat attending the meeting.
Analysts say that could be a signal of its reluctance to back tougher sanctions.
The UN Security Council, including China and Russia, has previously called for Iran to stop enriching uranium and has issued three sets of sanctions so far aimed to compel Tehran to stop uranium enrichment and scale back its nuclear program.
The United States and the EU believe Iran intends to built nuclear weapons, Tehran insists the program is only for peaceful energy purposes.