US will use UN veto to block any Russian sale of warplanes to Iran

The United States will use its veto power at the United Nations Security Council against Russia if the Kremlin goes ahead with a sale of advanced Su-30 fighter jets to Iran said the US Under-Secretary of State for Political Affairs Thomas Shannon on Tuesday. 

"We would block the approval of fighter aircraft," Shannon confirmed in a hearing with the US Senate Foreign Relations Committee. 

A US veto would block the sale since such a sale would need Security Council approval. 

"We've got a commitment ... from the Russians in terms of working to prohibit the transfer of technologies to Iran's ballistic missile program," Shannon explained. "They are complying with their commitment not to transfer these kinds of technology or to facilitate the transfer." 

Washington would also be receptive to renewing the Iran Sanctions Act at the end of the year provided it doesn't interfere with Washington's commitments under the Iran nuclear deal reached last July. 

Russia is geared to finally deliver S-300 air defense missile systems to Tehran following the lifting of sanctions in January. It had previously canceled its contract to deliver these missiles back in 2010 in compliance with UN sanctions against Iran's nuclear program. 

In addition to arms sales Washington is also opposed to Iran's continued testing of missiles saying they contravene a UN Security Council resolution passed last year which forbids Iran's development and testing of nuclear capable missiles. 

Iran however counters that its missiles are conventional, not designed to carry nuclear warheads and wholly defensive.