"Our intention is to confirm all previous decisions," Russian Foreign Minister Sergei Lavrov said after an impromptu meeting with his counterparts from the four other permanent Security Council members and Germany.
He was referring to three previous rounds of sanctions the world body slapped on Iran for its refusal to halt sensitive nuclear work.
British Foreign Secretary David Miliband said on the sidelines of the UN General Assembly: "We will be presenting a short resolution for consultations today that reaffirms existing resolutions and the unity of the E3+3."
The E3+3 group includes the European powers Britain, France and Germany and the remaining Security Council members China, Russia and the United States.
Miliband told reporters the six powers' agreement on the draft also showed "our determination to take forward that strategy with further discussions and further steps."
The six powers have been trying to convince Iran to abandon uranium enrichment amid Western fears that Tehran is seeking to build an atomic bomb.
Friday's meeting gained new urgency after the UN nuclear watchdog reported last week that Tehran continued to defy international pressure to cooperate with its investigation. Iran insists its nuclear program is strictly aimed at producing civilian energy.
German Foreign Minister Frank-Walter Steinmeier said the UN resolution could be passed by the Security Council as early as Saturday.
He welcomed the six countries' agreement on the text as "an important sign of unity on Iran" and noted the draft did not rule out future sanctions.
"The position of the international community remains that we want to say firstly, that we are ready to cooperate with Iran but secondly, only if Iran fulfills its commitments to the international community," he told reporters.
"If it does not, we are ready to go the other way, possibly toward further new sanctions. What is key, however, is that we are actually able to go down that road together, as the group of six."
Steinmeier rejected suggestions by some Western diplomats that it would be better to seek a raft of new bilateral sanctions against Iran rather than trying at all costs to keep China and Russia, which are more reticent, on board.
"I cannot imagine that destroying such formats and breaking off the dialogue (within the E3+3) would have led to more pressure on Iran," he said.
"My fear was that there was, or would have been, too much satisfaction in Iran if we had not made a joint declaration."
The ministers had initially planned to gather here Thursday to weigh new sanctions against Tehran.
But that meeting was called off after Moscow complained Washington sought to "punish" it, apparently over Georgia.
Moscow also cited US refusal to hold meetings this week of the Group of Eight industrial countries, composed of the United States, Russia, Canada, Japan, Britain, France, Italy and Germany.
"We do not see any fire that requires us to toss everything aside and meet to discuss Iran's nuclear program in the middle of a packed week at the United Nations General Assembly," the Russian Foreign Ministry said in a frosty statement.
The war with Georgia, a US ally, led to the worst chill in relations between Moscow and Washington since the Cold War and prompted US officials to say Russia could face isolation.
But the United States and Russia later appeared to climb down from the dispute, agreeing here to hold further ministerial-level meetings in the future on Iran's disputed nuclear program.
In his address to the UN General Assembly Tuesday, Iranian President Mahmoud Ahmadinejad vowed to pursue nuclear technology in the face of Western threats.
Iran "will resist the bullying and has defended and will continue to defend its rights," he said.
In a clear reference to Washington and its allies, the Iranian leader said: "They oppose other nations' progress and tend to monopolize technologies and to use those monopolies in order to impose their will on other nations."
