WASHINGTON: The United States posted a reward of up to $12 million on Thursday for help in tracking down two Iran-based al Qaeda financial backers, accused of funneling money to extremists in Syria.

The State Department named the men as Muhsin al-Fadhli and his deputy Adel Radi Saqr al-Wahabi al-Harbi, saying both “facilitate the movement of funds and operatives through Iran on behalf of the al Qaeda terrorist network.”

“Al Qaeda elements in Iran, led by Fadhli, are working to move fighters and money through Turkey to support al Qaeda-affiliated elements in Syria,” the department said in a statement.

“Fadhli also is leveraging his extensive network of Kuwaiti jihadist donors to send money to Syria via Turkey.” Fadhli, 31, was among the few al Qaeda leaders who was given advance notice that the group planned to strike the United States on September 1, 2001.

He is also alleged to have raised money to fund the October 2002 attack on the French ship MV Limburg off the coast of Yemen in which one person was killed, and four crew members injured.

“Fadhli reportedly has replaced Ezedin Abdel Aziz Khalil (better known as Yasin al-Suri) as al Qaeda's senior facilitator and financier in Iran,” the statement said, offering up to $7 million for information on his location.

Fadhli is on Saudi Arabia's most wanted list after a series of al Qaeda attacks in the Gulf kingdom.

Harbi, 25, a Saudi national, was put on the Saudi list in 2011 charged with traveling to Afghanistan to join al Qaeda and providing Internet support to the group. The US is offering up to $5 million for his arrest.

The Treasury Department also slapped sanctions on Harbi, banning US nationals and companies from carrying out any transactions with him.

“Today's action, which builds on our action from July 2011, further exposes al Qaeda's critically important Iran-based funding and facilitation network,”said David Cohen, under secretary for terrorism and financial intelligence.

“We will continue targeting this crucial source of al Qaeda's funding and support, as well as highlight Iran's ongoing complicity in this network's operation,” he said.

Fadhli, who was born in Kuwait, is also wanted by Kuwaiti authorities after being convicted in his absence and sentenced to five years on charges of providing funding and training to terror groups in Afghanistan.