The agreement clears the way for a vote as early as Wednesday on the draft resolution, Reuters reported.
U.S. Defense Secretary Robert Gates said he is confident that the U.N. will approve new sanctions on Iran this week.
Gates says that would give a legal foundation for the United States, European Union or others to pile on even stricter penalties.
Both Gates and his new British counterpart, defense chief Liam Fox, said Tuesday that there is still time to stop Tehran from getting a nuclear bomb.
Following a meeting with Gates in London, Fox warned strongly that an Iranian nuclear weapon would start a Mideast arms race.
The Associated Press and Reuters contributed to this report.