WASHINGTON – Defense Secretary Rumsfeld said yesterday he does not know when America will have trained enough Iraqis so they can adequately secure the country and begin replacing U.S. troops now helping provide protection.

“It’s interesting to me that some people think they know that because it’s not knowable,” Mr. Rumsfeld said.

Discussing the two resignation letters he wrote President Bush at the height of the Abu Ghraib prisoner abuse scandal last year, Mr. Rumsfeld said he believed he still could be an effective Pentagon chief but wanted the president to make that call. “I told him I really thought he ought to carefully consider it. But he made a conscious decision, and life goes on, and here we are,” Mr. Rumsfeld told ABC’s “This Week.”

With speculation heating up about a possible American attack against Iran to derail its nuclear capability, Mr. Rumsfeld was asked if there were American military operations going on in the country now. “Not to my knowledge,” he replied.

The training of Iraqi security forces is one of the factors influencing the continued presence of American troops, which grew by 15,000 to 150,000 ahead of the January 30 elections in Iraq.

General Richard Myers, chairman of the Joint Chiefs of Staff, has told Congress that only about one-third of Iraq’s 136,000 trained security forces are capable of engaging combat with insurgents across the country.

Mr. Rumsfeld said yesterday there are too many unknown factors to be able to say when Iraqis will be able to handle internal security. It is uncertain, Mr. Rumsfeld said, to what extent “the political process is going to tip people away from supporting insurgency or being on the fence to supporting the government.”

Further necessary to undermining the insurgency is cutting off its financial support, which comes from Saddam Hussein’s loyalists and others, the secretary said.

Also yesterday, Mr. Rumsfeld said journalists were not told what to write when they were assigned articles about Europe for Pentagon-run Web sites. The practice is now under review by the military’s chief investigator.

“I’m told that in this case, people were just asked to prepare anything,” Mr. Rumsfeld said on CNN’s “Late Edition.” “They were asked to take a subject, and if they wanted to, write something on it, which people do all the time,” he said.

Inspector General Joseph Schmitz is reviewing the military’s practice of paying journalists to provide articles and commentary for a Web site aimed at influencing public opinion in the Balkans, said Larry Di Rita, Mr. Rumsfeld’s chief spokesman.

On the abuse scandal at Abu Ghraib prison near Baghdad, Mr. Rumsfeld said that as the Defense Department’s leader, he took responsibility.