U.S. trade reports show that American exports to Iran have grown sharply since 2001, even as the United States has called for tougher international sanctions against the Tehran government.

In a lengthy analysis of U.S.-Iranian trade Tuesday, the Associated Press says American exports to Iran have shown enormous growth since President George Bush took office in 2001, even though they remain only a tiny fraction of overall U.S. sales abroad.  

Exports to Iran last year were more than 10 times higher than during Mr. Bush's first year in office.  

U.S. officials have repeatedly accused Iran of trying to build a nuclear arsenal and of supporting terrorists.  

But the State Department said today that the trade exemptions, which allow some U.S. exports to reach Iran, may have a positive effect by helping integrate Iranian consumers into the world economy.

None of the shipments to Iran are described as illegal, but the AP study comments that U.S. government agencies do not appear to have coordinated policies on commercial trade with Tehran.

Since 2001, U.S. shippers have sent to Iran food, medical and industrial supplies and other goods worth nearly $550 million.  The number-one American export to Tehran has been cigarettes - $158 million worth, or over one-quarter of all shipments, and by value more than twice as much as the second-ranking export, vaccines.

Sanctions were first imposed against Iran in 1979 and broadened since then.  AP reports total export sales to Iran in 2007 were $146 million, compared to $8.3 million in 2001, during Mr. Bush's first year in the White House.

Last month, a U.S. Senate panel approved legislation that would tighten sanctions imposed against Iran in connection with its nuclear program.  Iran also is under three sets of limited U.N. Security Council sanctions for defying demands to stop enriching uranium - a process that can be used to produce nuclear weapons.