"I think they are prepared to do more" than the administration of President Barack Obama, he said. Obama was reluctant to commit large numbers of U.S. troops to combatting IS in Iraq, but his approach, which relied on training and supporting local forces, has succeeded in pushing the militants out of much of the territory they once held.
Speaking at a Washington think tank shortly after his White House visit, al-Abadi said he got the impression that the Trump administration will take a more aggressive approach, although he did not say what that might entail.
"I think this administration wants to be more engaged in fighting terrorism," he said. "I sense a difference in terms of being head-to-head with terrorism." He added, however, that military force is not necessarily the most effective tool. "There are better ways for defeating terrorism."
Asked whether he had seen specific Trump administration improvements to the previous administration's approach, al-Abadi said: "To be honest, I haven't seen a full plan. I know there is a plan. I haven't seen it. We have our own plan."
Defense Secretary Jim Mattis recently presented Trump with the outlines of a comprehensive approach to defeating IS and other extremist groups on a global scale, but specifics are yet to be worked out. Officials have indicated that the approach is unlikely to depart radically from the Obama strategy, at least with regard to the ongoing efforts in Iraq and Syria.
Al-Abadi appeared at the U.S. Institute of Peace, a federally funded think tank. The prime minister spoke optimistically of completing the recapture of Iraqi lands still held by IS. He said government forces, working effectively with Kurdish forces known as Peshmerga and supported by American airpower and military advisers, are on the brink of fully liberating Mosul, the northern city that has been the Islamic State group's main Iraqi stronghold since 2014.
He spoke later at a U.S. Chamber of Commerce dinner with U.S. business executives, along with Commerce Secretary Wilbur Ross.
In brief remarks in the presence of reporters during al-Abadi's White House visit, Trump raised his frequently stated objections to the Iran nuclear deal negotiated by his predecessor, but did not talk specifically about how he intends to support Iraq.
"One of the things I did ask is, 'Why did President Obama sign that agreement with Iran?' because nobody has been able to figure that one out," Trump said. "But maybe someday we'll be able to figure that one out."
Trump said he hopes to address the "vacuum" that was created when IS moved into Iraq and added that "we shouldn't have gone in" to Iraq in the first place.
In readout of the pair's meeting, the White House said the United States and Iraq "stand fully committed to a comprehensive partnership, rooted in mutual respect" and agreed to "pursue a long-term partnership to decisively root out terrorism from Iraq and strengthen the Iraqi military and other key institutions."
"Although ISIS/Da'esh remains a dangerous enemy, we are confident it will be defeated," they said.
Trump campaigned on a promise to dramatically ramp up the assault on IS and has vowed to eradicate it.
Trump greeted al-Abadi in the Oval Office shortly after FBI Director James Comey said the FBI and Justice Department have no information to substantiate Trump's claims that Obama wiretapped him before the election. As reporters were leaving, al-Abadi leaned over to Trump and said jokingly, "We have nothing to do with the wiretap."
In his think tank appearance later, al-Abadi again struck a humorous note at Trump's expense. After expressing hope that Iraq will succeed in ending decades of internal conflict, he said his country should be wary of partitioning areas along ethnic or religious lines as some have recommended.
"We have to build bridges with others and work with others to be more secure," he said. "Otherwise, what do you do? You build walls? What do you do?" He then grinned widely at the allusion - intended or not - to Trump's plan to erect a wall on the border with Mexico.
Later this week al-Abadi will be attending a 68-nation meeting to discuss the coalition against the Islamic State group.
Associated Press writer Lolita Baldor contributed to this report.
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