(Adds detail on Ba'asyir, Rahman, sanctions)
WASHINGTON Aug 16 (Reuters) - U.S. officials said on Tuesday the government tried to cut off the funding for a key suspect in the 2002 Bali bombing and two other senior members of the southeast Asian terrorist network Jemaah Islamiah.
Umar Patek, who is accused of planning attacks on a nightclub in Bali, will be blacklisted by the United States along with Abdul Rahim Ba'asyir and Muhammad Jibril Abdul Rahman.
The sanctions are designed to cut off the suspects' ability to access the international finance system by prohibiting U.S. transactions with the three men.
They have "demonstrated their commitment to violence," David Cohen, Treasury Department undersecretary for terrorism and financial intelligence, said in a statement.
Al Qaeda is believed to have supported some of Jemaah Islamiah's (JI) attacks, including the Bali bombings that killed more than 200 people.
Patek, a bombmaker for JI, was recently extradited from Pakistan to Indonesia and is one of the few Indonesian militants who is expected to explain the connections between Islamist militant groups in Asia.
According to the U.S. Treasury, Patek obtained funding for operations that were to include a car bombing in Manila, attacks on Philippine military camps and assassinations of prominent foreigners.
Any assets the three men may hold under U.S. jurisdiction are frozen, the U.S. Treasury said on Tuesday.
Ba'asyir is one of JI's leaders, who served as the Southeast Asian network's main contact with al Qaeda from the late 1990s to mid-2002. He has also been involved in JI's outreach to Pakistan-based separatist group Lashkar-e-Taiba, which is also known for its links to al Qaeda and was blamed for the 2008 Mumbai attacks that killed 166 people.
The third senior member who was sanctioned, Rahman, has been involved in obtaining funding for terrorist attacks, Treasury said.
(Reporting by Rachelle Younglai; Editing by Jeffrey Benkoe and Chizu Nomiyama)