US President Barack Obama is to set out his “game plan” against Islamic State militants in a speech on Wednesday.
Mr Obama, who has been criticised for failing to outline a strategy, told NBC TV the US would degrade IS, shrink their territory and “defeat them”.
US jets bombed IS targets in western Iraq for the first time on Sunday.
Meanwhile, the Arab League has vowed to take “all necessary measures” against IS, which has seized a huge amount of territory from Iraq and Syria.
The League gave its backing to a Security Council resolution passed last month calling on member states to stem the flow of weapons and money to extremists in Iraq and Syria.
BBC World Service Middle East editor Sebastian Usher says the Arab League’s message will hearten Mr Obama, but the question now is whether its members will fully act on it, and act together rather than against each other.
‘No ground troops’
Speaking on NBC’s Meet the Press, Mr Obama said: “I’m preparing the country to make sure that we deal with a threat from Isil.”
IS, also often referred to as Isil or Isis, has taken over large swathes of Iraq and Syria in recent months, declaring the land it holds a “caliphate”.
Mr Obama went on: “On Wednesday, I’ll make a speech and describe what our game plan’s going to be going forward.”
He said he would “start going on some offence” against IS.
But the strategy was “not going to be an announcement about US ground troops”, he added.
He said: “This is not the equivalent of the Iraq war. What this is, is similar to the kinds of counterterrorism campaigns that we’ve been engaging in consistently over the last five, six, seven years.
“I just want the American people to understand the nature of the threat and how we’re going to deal with it and to have confidence that we’ll be able to deal with it.”
Mr Obama said the strategy would not involve the US alone but would be one pursued by an international coalition.
He said: “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.”
The interview was conducted on Saturday, shortly after Mr Obama returned from the Nato summit in Wales, where the grouping agreed to take on IS.
Mr Obama made his “no strategy” comment last month when asked whether he needed Congress’s approval to “go into Syria”.
BBC North America editor Jon Sopel says that while it showed how complex the situation in the region was, it also showed the extreme wariness of the president to unilaterally start military action when it was not clear where it would end.
Sunday’s four US air strikes were aimed at protecting Iraqi forces and Sunni tribesmen who are in control of Haditha dam.
Analysis: Jim Muir, BBC News, northern Iraq
The American air attacks, the first of their kind in Anbar province, signal that Washington has crossed a line that it itself drew.
It has long had a standing request from the outgoing Iraqi government to use its air power against IS in all areas. But until recently, it made it clear it would only do that once a new, inclusive government is formed in Baghdad, with full Sunni representation.
That hasn’t yet happened, though intensive efforts are under way to produce a new cabinet in the coming days.
Fighter and bomber aircraft destroyed five Humvees, one IS armed vehicle and an IS checkpoint, and also damaged an IS bunker, the US military said.
The US has carried out more than 130 air strikes since early August to support Iraqi and Kurdish forces fighting IS in northern Iraq, but these were the first in Anbar.
US Defence Secretary Chuck Hagel said: “If that dam would fall into [Islamic State’s] hands or if that dam would be destroyed, the damage that that would cause would be very significant.”
Islamic State fighters have targeted a number of dams in their offensive, capturing the facility at Fallujah.
They also took the largest dam, at Mosul, but US air strikes helped force them out.
The group has so far failed in its attempts to capture Haditha dam, on the Euphrates valley. It is Iraq’s second largest dam.
Separately, the governor of Anbar, Ahmed al-Dulaimi, was wounded in fighting in the province, the army said.
It said a mortar round had wounded Mr Dulaimi in the town of Barwana shortly after it was retaken from IS on Sunday.