WASHINGTON: Democratic presidential hopeful Barack Obama insisted Thursday he had not changed his plan for immediate troop withdrawals from Iraq, despite earlier saying he might refine his policies.

Obama spoke to reporters for a second time Thursday in North Dakota, four hours after his remarks sparked reports, ahead of a planned visit to Iraq, that he was softening his plan to get all combat troops home within 16 months.

"I have seen no information that contradicts the notion that we can bring our troops out safely at a pace of one to two brigades per month," Obama said.

"This is the same position that I had four months ago, it's the same position that I had eight months ago. It's the same position that I had 12 months ago."

"My first day in office, I will bring the Joint Chiefs of Staff in, and I will give them a new mission, and that is to end this war. "Responsibly, deliberately, but decisively."

In an earlier meeting with reporters, Obama said he may "refine" his policies after consultations with generals on a trip to Iraq this month, details of which have not been announced for security reasons.

Obama, who based his primary campaign on vehement opposition to the Iraq war, said he would conduct a "thorough assessment" of his policies after the trip, his first to Iraq for two years.

The Illinois senator has faced fierce pressure from Republican foe John McCain over Iraq, who has said Obama should change his plans to take account of apparent security gains wrought by the recent US troop-surge strategy.

"When I go to Iraq and have a chance to talk to some of the commanders on the ground, I am sure I'll have more information and will continue to refine my policies," Obama was quoted as saying earlier by foreign media.

"I've always said that the pace of withdrawal would be dictated by the safety and security of our troops and the need to maintain stability, that assessment has not changed."