The Mexican chairwoman at the meeting of the International Atomic Energy Agency's (IAEA) 35-nation board of governors, Patricia Espinosa Cantellano, said "negotiations are still ongoing" on the resolution.
She postoned discussion on agenda item 8d -- Nuclear Verification Implementation of the nuclear Non-Proliferation Treaty safeguards agreement in the Islamic Republic of Iran, the spokesman said.
"We hope in the next few days to deal with this item," Espinosa Cantellano said, according to the spokesman said.
The IAEA board meeting was supposed to end Friday, but there was opposition to a compromise US-European draft resolution which was finalized late Thursday.
The spokesman said no time has yet been set for the debate on Iran to resume.
The United States bowed to pressure from Europe by dropping an ultimatum over Iran's alleged nuclear weapons program but non-aligned nations, as well as Russia and China, apparently feel the wording is still too tough.
Washington and the so-called Euro 3 -- Britain, France and Germany -- set a November deadline for a full review of Iran's nuclear program but also called on Tehran to "immediately" suspend all uranium enrichment activities, according to a copy of a draft resolution obtained by AFP.
Iranian delegation chief Hossein Mousavian said Iran would decide within two or three days and based on its "national interests," whether to respect the IAEA call or resume this key part of the nuclear fuel cycle.
Malaysia's IAEA ambassador Hussein Haniff, spokesman for the non-aligned, said that "if the resolution stays (as it is), there will be no consensus" at the board, which usually passes such texts unanimously.
Despite such objections, the IAEA board usually adopts US-European compromises but often after minor changes and extended debate.
This time the debate threatens to spill over to next week, when the IAEA is holding a general conference in Vienna.
"It would be a logistical nightmare," a Western diplomat said if the IAEA board fails to agree on a resolution by Saturday.