The head of Iran's atomic energy organisation, Mohammad Eslami, has arrived in Moscow for talks, Russia's state-run RIA news agency quoted the Iranian embassy as saying on Monday.
The 15-member U.N. Security Council earlier opted not to permanently lift sanctions on Tehran, after three European countries launched a 30-day process last month to reimpose them, accusing Tehran of failing to abide by a 2015 deal with world powers aimed at preventing it from developing a nuclear weapon.
Iran denies having any such intention, and Russia says it supports Tehran's right to peaceful nuclear energy.
Eslami is also Iran's vice president. RIA did not say whom he would meet in Moscow.
Reporting by Marina Boborova