BAGHDAD U.S. and Iraqi commanders on Saturday hailed a big improvement in security over the past year, while al Qaeda leader Osama bin Laden accused the Americans of seeking to exploit Iraq's oil wealth.
The top American general in Iraq said progress had been made in curbing attacks and civilian deaths, but warned that the gains could be reversed.
"Success will emerge slowly and fitfully with reverses as well as advances. Inevitably there will be tough fighting, more tough days and more tough weeks, but fewer of them, inshallah (God willing)," General David Petraeus said in a year-end briefing to journalists.
In a message to his troops, he wrote: "A year ago, Iraq was racked by horrific violence and on the brink of civil war.
"Now, levels of violence and civilian and military casualties are significantly reduced and hope has been rekindled in Iraqi communities. To be sure, the progress is reversible and there is much more to be done."
Iraqi Interior Ministry spokesman Major-General Abdul-Karim Khalaf said 75 percent of Sunni al Qaeda networks and 70 percent of its activities had been eliminated.
In a statement posted on the Internet, al Qaeda leader bin Laden urged Iraqis not to join counter-insurgency patrols -- predominantly Sunni Arab tribal police funded by the U.S. military to fight al Qaeda and reduce violence.
Bin Laden also accused the United States of plotting to take control of Iraq's oil wealth and called on Iraqis to reject efforts to rebuild a U.S.-backed national unity government.
"America seeks alongside its agents in the region to create an allied government ... that would accept in advance the presence of major U.S. bases in Iraq and give the Americans all they wish of Iraq's oil," he said.
WHITE HOUSE CONDEMNS BIN LADEN
Sunni Arabs pulled out of Prime Minister Nuri al-Maliki's Shi'ite-led government earlier this year, accusing it of being too sectarian.
Maliki flew to London on Saturday for what he said was a routine medical checkup, but an official in his office said it was treatment for exhaustion.
The official said Maliki, 57, would also undergo a series of routine checkups, including tests on his heart.
"He is suffering from mild exhaustion. He is also going to have a heart scan," the official said.
U.S. officials are concerned that slow progress towards reconciliation between Shi'ites and Sunnis could erode security gains.
U.S. counter-terrorism officials said they were checking the authenticity of the bin Laden statement, but had no reason to doubt it was the Saudi-born militant accused of masterminding the September 11 attacks on the United States.
The White House condemned the bin Laden statement.
"This is a reminder that the aim of al Qaeda in Iraq is to block democracy and freedom for all Iraqis. It also reminds us that the mission to defeat al Qaeda in Iraq is critically important and must succeed," White House spokesman Tony Fratto said in an emailed statement.
Although the security situation has improved this year, U.S. commanders have been careful not to declare victory after years in which their statements were often seen as overly optimistic.
Petraeus said tactics should now shift from a focus on security toward civilian aims, such as helping Iraq restore services and create jobs, to prevent violence from returning.
The decline in violence came about after Washington sent 30,000 extra troops to Iraq this year. Withdrawals are now under way that will see numbers decline to about pre-surge levels by mid-2008.
U.S. commanders say they will decide troop levels beyond that after an assessment in March. Petraeus said U.S. forces would not withdraw entirely from areas but "thin out" their presence and gradually hand control to Iraqi forces.
(Additional reporting by Ross Colvin and Aseel Kami in Baghdad, Inal Ersan in Dubai and Paul Eckert in Washington; Writing by Keith Weir; Editing by Stephen Weeks)