The US may be able to reduce combat forces in Iraq by next spring, if Iraq's own security forces continue to grow and improve, a senior American commander said Friday. He denied reports that the US is arming Sunni insurgent groups to help in the fight against al-Qaida. Lt. Gen. Raymond Odierno, the top day-to-day commander of US forces in Iraq, did not predict any reductions in U.S. forces but said such redeployments may be feasible by spring. There are currently 156,000 US troops in Iraq. Speaking to reporters at the Defense Department from his headquarters outside Baghdad, Odierno gave an update on the US offensives under way in Diyala province northeast of Baghdad and in areas south and west of the capital. He said US and Iraqi troops have made important progress. "I think if everything goes the way it's going now, there's a potential that by the spring we will be able to reduce forces, and Iraq security forces could take over," Odierno said. "It could happen sooner than that. I don't know."