U.S. restraint in Syria seen as key to Iran nuke talks

WASHINGTON -- President Barack Obama's reluctance to give military aid to Syrian rebels may be explained, in part, in three words: Iranian nuclear weapons.

For the first time in years, the United States has seen a glimmer of hope in persuading Iran to curb its nuclear enrichment program so it cannot quickly make an atomic bomb. Negotiations resume this week in Almaty, Kazakhstan, where encouraging talks in February between six world powers and the Islamic Republic ended in what Iranian diplomat Saeed Jalili called a "turning point."

But Tehran is unlikely to bend to Washington's will on its nuclear program if it is fighting American-supplied rebels at the same time in Syria. Tehran is President Bashar Assad's chief backer in the civil war. Iranian forces are believed to be fighting alongside the regime's army. A senior commander of Iran's elite Revolutionary Guard force was killed outside Damascus in February.

Russia also is supplying Assad with arms. The United States does not want to risk alienating Russia, one of the six negotiating nations, by entering what would amount to a proxy war in Syria. The White House has at least for now put the nuclear negotiations ahead of intervening in Syria, according to diplomats, former Obama administration officials and experts. -- AP