The United States on Monday said it welcomed new European Union economic sanctions aimed at pressuring Iran into halting any nuclear weapons development.

"Rallying the world to isolate Iran and increasing the pressure on its leadership so that they stop pursuing a nuclear weapon has been a top priority for the president," White House spokesman Jay Carney told reporters traveling with the president.

European Union governments agreed to further economic sanctions against Iran's banking, shipping, and industrial sectors on Monday, hoping to pressure Iran into serious negotiations on its nuclear program.

The move "further strengthens international efforts to pressure and isolate the Iranian government," Carney said.

The new sanctions mark one of the toughest moves against Iran by Europe to date and a significant change of policy for the 27-member bloc, which until now had focused on targeting specific people and companies with economic restrictions.

The EU has lagged the United States in imposing blanket industry bans because it wants to avoid punishing ordinary Iranian citizens as it tries to inflict pain on the Tehran government.

Iran maintains that its nuclear project has only peaceful energy purposes and has refused in three rounds of talks since April to scale back its uranium enrichment activity unless major economic sanctions are rescinded.