That’s been widely understood, but this is the highest ranking U.S. official to confirm it and this fact hasn’t been pointed out in months.
From MEMRI:
In the third day of hearings at the Iraqi parliament, Iraqi Interior Minister Jawad Al-Bolani is reported to have revealed in the secret hearings that the cellphone call record of the suicide bomber who blew up the Foreign Ministry last August indicates that he made his last call to someone in Damascus before the operation.
In a related matter, General David Petraeus, U.S. CENTCOM head, told Al-Arabiya TV that Izzat Al-Douri, deputy to Saddam Hussein and one of the men most wanted by the Iraqi government, is in Damascus.
[In his youth, Al-Douri sold ice blocks from a horse-drawn cart; he is known in Iraq as "The Iceman"]
Sources: Al-Mada, December 15, and al-Rafidayn, December 14, 2009