President Obama is expected to address the nation Wednesday about a multi-year plan to combat the Islamic State of Iraq and Syria according to a report by The New York Times.

The President will meet with with House and Senate leaders Tuesday to outline the administration's plan to deal with ISIS. Phase One of the offensive is currently underway, with more than 140 air strikes having been carried out against ISIS forces since August 8.

Phase Two will involve intensified efforts to equip and train the Iraqi Army, Kurdish fighters and Sunni tribesmen willing to set aside grievances with the current Iraqi government in order to expel ISIS from the region. This phase is set to begin after Iraq forms a new government, which is expected to happen later this week.

Phase Three will reportedly involve carrying out airstrikes against ISIS forces in Syria, something Bashar Assad's government warns will not happen without their permission. It is unclear how the Obama administration plans to obtain a go-ahead from the Syrian government before carrying out strikes.

In an interview aired Sunday during NBC'S 'Meet the Press', Obama stated that plan does not include a surge of American troops, and stressed that any action taken will be in support of Iraqi forces.

"We're not looking at sending in a hundred thousand American troops," he said. "We are going to be, as part of an international coalition, carrying out airstrikes in support of work on the ground by Iraqi troops - Kurdish troops. We are going to be helping to put together a plan for them so that they can start retaking territory that ISIL had taken over."

"What I want people to understand is that over the course of months, we are going to be able to not just blunt the momentum of ISIL. We are going to systematically degrade their capabilities, we're going to shrink the territory that they control, and, ultimately, we're going to defeat them."

When asked if ISIS posed as great a terrorist threat as those responsible for the 9/11 attacks, Obama said, "Not yet, but they can evolve."

Obama's remarks followed a two-day NATO summit in Wales, where the U.S. and nine European allies agreed to take action against ISIS due to the potential terror threat they pose.

The plan proposed by the administration is expected to be a long-term commitment that could extend beyond Obama's term.

“It’s going to take time, and it will probably go beyond even this administration to get to the point of defeat," deputy national security adviser Antony J. Blinken told CNN last week. According to Sunday's New York Times article, some Pentagon planners expect the  military campaign to last at least 36 months.