New infusions of US Marines will begin moving into Afghanistan almost as soon as US President Barack Obama announces a redrawn battle strategy, a plan widely expected to include more than 30,000 additional US forces. Obama will try to sell a skeptical public on his bigger, costlier war plan Tuesday by coupling the large new troop infusion with an emphasis on stepped-up training for Afghan forces that he says will allow the US to leave. Obama formally ends a 92-day review of the war in Afghanistan Tuesday night with a nationally broadcast address in which he will lay out his revamped strategy from the US Military Academy at West Point, NY. He began rolling out his decision Sunday night, informing key administration officials, military advisers and foreign allies in a series of private meetings and phone calls that stretched into Monday. Military officials said at least one group of Marines is expected to deploy within two or three weeks of Obama's announcement, and would be in Afghanistan by Christmas. Larger deployments wouldn't be able to follow until early in 2010. The initial infusion is a recognition by the administration that something tangible needs to happen quickly, officials said. The quick addition of Marines would provide badly needed reinforcements to those fighting against Taliban gains in the southern Helmand province, and could lend reassurance to both Afghans and a war-weary US public. Secretary of State Hillary Rodham Clinton, in remarks Monday to business executives in New York, stressed that the administration's strategy is to go after not just the al-Qaida terror network but also the Taliban militants allied with it in Afghanistan and Pakistan. "As long as Afghanistan and Pakistan struggle to control their borders and extend their sovereignty to all their territory, the door is open to bad actors, and the result can be an environment in which terrorist groups thrive," she said. The war escalation includes sending 30,000 to 35,000 more American forces into Afghanistan in a graduated deployment over the next year, on top of the 71,000 already there. Obama's announcement is the culmination of more than three months of debate over whether and how to expand US military involvement in a war that has turned worse this year despite Obama's previous infusion of 21,000 forces. Obama also will deliver a deeper explanation of why the US must continue to fight more than eight years after the war's start, emphasizing that Afghan security forces need more time, more schooling and more US combat backup to be up to the job on their own. He will make tougher demands on the governments of Pakistan and, especially, Afghanistan, and will provide a fresh path toward disengagement. "This is not an open-ended commitment," White House press secretary Robert Gibbs said Monday. "We are there to partner with the Afghans, to train the Afghan national security forces, the army and the police, so that they can provide security for their country and wage a battle against an unpopular insurgency." With US casualties in Afghanistan sharply increasing and little sign of progress, the war Obama once liked to call one "of necessity," not choice, has grown less popular with the public and within his own Democratic party. In recent days, leading Democrats have talked of setting tough conditions on deeper US involvement, or even staging outright opposition. The displeasure on both sides of the aisle was likely to be on display when congressional hearings on Obama's strategy get under way later in the week on Capitol Hill. Obama was spending much of Monday and Tuesday on the phone, outlining his plan - minus many specifics - for the leaders of France, Britain, Germany, Russia, China, India, Denmark, Poland and others. He also met in person at the White House with Australian Prime Minister Kevin Rudd. A briefing for dozens of key lawmakers was planned for Tuesday afternoon, just before Obama was set to leave the White House for the speech against a military backdrop at West Point. The Afghan government said Tuesday that President Hamid Karzai and Obama had an hourlong video conference. Obama was also going to speak with Pakistani President Asif Ali Zardari. In Afghanistan, rampant government corruption and inefficiency have made US success much harder. Obama was expected to place tough conditions on Karzai's government, along with endorsing a stepped-up training program for the Afghan armed forces along the outline recommended this fall by US trainers. That schedule would expand the Afghan army to 134,000 troops by next fall, three years earlier than once envisioned. Military officials said the speech is expected to include several references to Iraq, where the United States still has more than 100,000 forces. The strain of maintaining that overseas war machine has stretched the Army and Marine Corps and limited Obama's options. Obama outlined the contours of his plan to German Chancellor Angela Merkel, according to her spokesperson. Earlier Tuesday, Merkel had told reporters that Germany would await the results of an international conference on Afghanistan next month in London before deciding whether to commit more forces. About 4,000 German soldiers are currently deployed in Afghanistan as part of the NATO-led force.