The European Union on Friday tightened trade sanctions against Iran to punish Tehran for not committing to a long-standing demand of the international community that it freeze its nuclear enrichment program.

The new EU restrictions go slightly beyond existing U.N. trade sanctions and are designed to deny public loans or export credits to companies trading with Iran.

France, the current holder of the EU presidency, said European governments would also carefully watch financial groups doing business with Iranian banks and step up checks on ships and airplanes traveling to Iran.

"This resolution expands the range of restrictive measures adopted by the U.N. Security Council," in December 2006 and March 2007, an EU statement said.

The EU called on member nations to "show restraint when granting new public loans for trade with Iran ... to also be vigilant on activities taken by financial institutions with banks based in Iran."

The announcement came three days after France and the United States called insufficient Iran's response to an international effort to defuse a dispute over its nuclear program.

They said Iran has skirted the central question of whether it was ready to halt uranium enrichment that western nations see providing Tehran with nuclear weapons technology.

The new sanctions expand existing limits on trade with Iran beyond the United Nations Security Council's three sets of limited sanctions that monitor trade and banking. But they do not go as far as sanctions on Iran's oil and gas trade which EU ministers threatened in June.

EU countries will inspect airplanes and ships traveling to and from Iran to check that they are not carrying contraband goods to the country. France said they would focus on Iran Air Cargo and the Islamic Republic of Iran Shipping Line.

European governments will also monitor banks dealing with Bank Saderat, an Iranian bank with purported links to suspect Iranian nuclear activities.

The five permanent members of the U.N. Security Council and Germany have tried to entice Iran into suspending uranium enrichment by offering a package of economic, technological and political incentives.

Iran said Tuesday that it would only give a clear response to this offer when it gets a clear response on questions it has about the incentives.

The United States and others accuse Iran of trying to develop nuclear weapons under cover of a civilian atomic energy program. Iran denies the charge, insisting its program is peaceful, but it has thus far refused to halt enriching uranium, a process that can produce the ingredients for a bomb.

Iran currently is under three sets of U.N. Security Council sanctions and could soon face a fourth unless it accepts the incentives package.