International pressure is growing for new sanctions against Iran following Tehran's announcement that it intends to step up its enrichment of uranium.
In Paris Monday, U.S. Defense Secretary Robert Gates and French President Nicolas Sarkozy said they will push for strong new sanctions.
Konstantin Kosachev, chairman of the international affairs committee of the State Duma, Russia's lower house of parliament, said the international community should react to Iran's move with serious measures.
The U.N. Security Council has already imposed three sets of sanctions on Iran over its nuclear program, which Western countries suspect is being used for weapons purposes.
U.S. officials said they hope to bring a sanctions resolution to the Security Council this month, while France holds the rotating presidency.
Iran said earlier Monday it has told the U.N. nuclear agency of its plan to enrich uranium to higher levels, defying calls by world powers for a halt to enrichment.
Tehran says its nuclear program is for peaceful purposes, and that it needs uranium enriched to 20 percent to fuel a medical research reactor. World powers fear Iran is trying to develop nuclear weapons.
The U.N. had brokered a deal with a group of world powers calling for Tehran to ship its uranium abroad for enrichment and having it returned to Iran as reactor fuel. But Iran had given mixed signals about its willingness to accept the deal.
Some information for this report provided by AP, AFP and Reuters.