Russia on Friday called the latest round of talks on the Iranian nuclear standoff "constructive" despite big differences that remain as the parties head for more negotiations in Moscow next month.
However, Russia outlined no new initiatives that could be discussed following a bruising session in Baghdad that ended with Iran declaring its "absolute right" to enrich uranium despite fears it was actually building a nuclear bomb.
"The round was held in a constructive and business-like atmosphere despite the significant differences in approaches that remain," the Russian foreign ministry said in a statement.
Iran and the six big world powers held what negotiators called open and intense talks that produced no breakthroughs and almost ended with Iran walking away in fury at Western offers on the table.
But the parties did salvage an agreement to meet again in Moscow on June 18-19 as the July 1 deadline for the enforcement of an EU embargo on Iranian oil looms.
Russia said world powers offered Iran a set of "concrete proposals" in Baghdad concerning its controversial enrichment of uranium to 20 percent.
Moscow's statement did not specify what the offer included amid reports that it concerned providing Tehran better access to aviation parts and agricultural assistance but not the lifting of UN Security Council and unilateral sanctions.
The six world powers "also designated specific initiatives that provide positive incentives for Iran as a reciprocal measure," the Russian statement said.
The wording suggested these sweeteners would be delivered to Iran only after it took the initial step of halting its controversial enrichment programme and shipping the fuel already produced abroad.
"For its part, Iran declared its readiness to hold further discussions about the 20-percent enrichment issue, together with the discussion of an entire range of other issues of interest to Tehran, including the recognition of its right to enrich (uranium)," the Russian statement said.
Moscow has promoted a "step-by-step" solution to the crisis that involves gradually lifting four rounds of UN Security Council sanctions against its trading partner in exchange for Tehran's cooperation over its nuclear programme.
It outlined the initiative to Iran's visiting foreign minister Ali Akbar Salehi in Moscow in August and has since promoted it with sceptical officials in Washington.
But Iran has yet to formally accept the Russian formula and insisted that unilateral and UN sanctions be lifted before it makes any concessions on its part.
Moscow's statement said Russian negotiator Sergei Ryabkov held separate talks in Baghdad with his Chinese and Iranian counterparts in an attempt to find common ground.
Both Russia and China have condemned the EU oil embargo and been far more supportive of Iran than the United States or the European team comprised of Britain and France along with Germany.
Russia has defended its close military and trade ties with Iran as well as its decision to construct the Islamic state's first nuclear power plant.
But it has also been more critical of Tehran's behaviour in the past year and decided to shelve the deal to sell its advanced warhead system to Iran that was opposed by the United States and Israel.
The Moscow statement said world powers were still seeking to "completely restore trust" in Iran's nuclear work.