Russia put pressure on Iran Wednesday by noting that it expected to see "serious progress" made at this month's talks in Kazakhstan over Tehran's disputed nuclear programme.
Deputy Foreign Minister Sergei Ryabkov said world powers and the Islamic republic had made no progress since the last round of top-level negotiations were held in Moscow at the end of June 2012.
But he stressed that pressure will be high on sides to climb down from their respective positions and seek middle ground at the February 26 meeting in Almaty.
"Despite everything, I would very much hope to see the upcoming round result in -- if not an outright breakthrough -- then serious progress," Ryabkov said in a wide-ranging interview with the state-run RIA Novosti news agency.
"Because so far, we have not advanced past the stage at which we found ourselves in June" in Moscow.
"We have lost a lot of time," Russia's top nuclear negotiator said.
"We do not think you can lose time anymore."
Talks between Iran and the so-called P5+1 powers -- the five permanent UN Security Council members and Germany -- have been held on three occasions at the highest level in the past year.
None of the meetings has drawn a promise from Tehran to scale back its contested nuclear enrichment programme to levels that world powers believe cannot be used to make atomic weapons.
Iran denies the programme has a military component and insists on global recognition of its right to enrich uranium for peaceful purposes.
World powers counter that Iran sacrificed its enrichment rights by refusing cooperation with international nuclear inspectors.
The dispute has resulted in four rounds of global sanctions against Tehran -- in addition to unilateral US and EU measures -- that have crippled the Iranian economy and hit its oil exports.
Ryabkov agreed that the meeting in Almaty would mostly show "whether there was a political will or not."
Ryabkov said the timing -- in the wake of the US presidential election season and ahead of Iranian polls -- meant that this might the last chance the two sides had to agree diplomatically for some time.
"The calendar itself is pressing us to work with greater intensity," Ryabkov said.
The new talks were confirmed this week after months of delays and complaints by the office of EU foreign policy chief Catherine Ashton -- the leading negotiator for the powers -- of Iran presenting a series of new preconditions for the talks to begin.
Some politicians and experts see the Almaty meeting as primarily a trust-building excercise that had only the most limited chances of reaching an actual deal.
The Moscow negotiations broke down over Iran's demand on the West to lift sanctions before it makes any compromise on enrichment levels.
The big nations offered an easing of sanctions as a reward for Iran's cooperation on enrichment instead.
Analysts do not believe that either side is currently willing to make the first move -- a view indirectly confirmed on Wednesday by Tehran's Moscow ambassador Mahmoud Reza Sajjadi.
"We made five proposals at the Moscow talks. Now we are waiting for their response," the Iranian ambassador said, quoted by Russian news agencies.
"Our main request at the upcoming talks is that there are no double standards about the Iranian nuclear programme," Sajjadi said.
The Kazakh meeting will also present Iranian and US negotiators to discuss Washington's latest proposal for direct negotiations with Tehran.
Iran has previously rejected such offers and has been non-committal about the latest direct discussions proposal voiced by US Vice President Joe Biden in Munich last weekend.