Washington ? The presence of several thousand extra U.S. troops in Baghdad in recent weeks showed that sectarian violence can be quelled by force of arms. But Defense Secretary Donald Rumsfeld said the gains will be lost unless the Iraqi government reconciles rival religious sects.

“There … is no question but that you can go in and clear out an area and achieve a reduction in violence, and the test is not that,” Rumsfeld told reporters in a joint appearance Friday at the Pentagon with Iraqi Deputy President Adil Al-Mahdi.

“The test is what happens thereafter. And the important thing is for the Iraqi government to achieve success with respect to its reconciliation process,” he said. “It’s important that they deal with the militia issue.”

Earlier this month, U.S. commanders sent an additional 5,500 U.S. troops into Baghdad from elsewhere in Iraq to conduct a series of security sweeps, after an initial Iraqi crackdown failed to reduce the level of violence.

Rumsfeld said he had a long telephone conversation Friday morning with Gen. John Abizaid, the top U.S. commander in the Middle East, and Gen. George Casey, the top commander in Iraq, about events in Baghdad.

Defense Secretary Donald Rumsfeld puts his hand over his head as Iraqi Deputy President Adil Al-Mahdi, not pictured, speaks with members of the media Friday at the Pentagon.

He said those talks reinforced his impression that since late July the extra efforts in Baghdad “have been successful in the sense that we’re seeing a reduction in the levels of violence and in the numbers of attacks.”

Rumsfeld was asked by a reporter whether the success thus far in reducing sectarian killings in Baghdad proves the broader argument that a bigger U.S. force throughout Iraq would stabilize the country faster.

He said it is apparent that a bigger U.S. force “does do it, for a period.” But he added, “What is important is for the Iraqi people and the Iraqi security forces and the Iraqi government, ultimately, to deal with this problem.”

Al-Mahdi told reporters he was pleased by the gains against sectarian violence in Baghdad in recent weeks.

“Baghdad is a key issue, and this is our response, our answer to all of those talking about civil war in Iraq,” Al-Mahdi said. “We don’t think we are leading to one.”

The deputy president said he also met with President Bush and Vice President Dick Cheney.