SYDNEY (AP) — In their first joint appearance abroad, America's top diplomat and its Pentagon chief offered public reassurances to a longstanding ally at odds with President Donald Trump's abandonment of the Paris climate agreement.

With Defense Secretary Jim Mattis at his side, Secretary of State Rex Tillerson told a news conference Monday that Trump is interested in "perhaps a new construct of an agreement," signaling that Trump believes the climate change issue "is still important and that he wants to stay engaged on the issue."

"He's not walking away from it," Tillerson said. "He's simply walking away from what he felt was an agreement that did not serve the American people well."

Julie Bishop, the Australian foreign minister, deflected any suggestion of a loss of confidence in U.S. leadership, saying, "We have a similar world view, we have shared values and shared interests" in other areas.

A reporter asked Tillerson to reconcile the administration's emphasis on strengthening alliances in Asia and elsewhere with what some perceive as isolationism in Trump's rejection of multilateral trade agreements, criticisms of NATO and abandonment of the Paris climate deal.

"That's why we're here," Tillerson said. "That's why we traveled here. That's why we engaged with our counterparts," adding, "So I hope the fact that we're here, demonstrates that it certainly is not this administration's view or intention to somehow put at arm's length the important partners and allies in the world."

Mattis called Australia "a beacon of hope for people and the world."

Even as the U.S. and Australian officials were meeting behind closed doors, news broke of a growing political rift among key American allies in the Persian Gulf.

Bahrain, Egypt, Saudi Arabia and the United Arab Emirates all announced they would withdraw their diplomatic staff from Qatar over that country's support for Islamist groups and its relations with Iran. Qatar is home to a U.S. military base that is central to the coordination of its air campaigns in Iraq, Syria and Afghanistan.

"I think what we're witnessing is a growing list of irritants in the region that have been there for some time, and obviously they have now bubbled up to level that countries decided they needed to take action in an effort to have those differences addressed," Tillerson said, noting that he had just heard news of this development. "We certainly would encourage the parties to sit down together and address these differences."

Tillerson said he did not believe this would have any impact on the fight against Islamic extremism.

Mattis was even more emphatic on the point.

"I am confident there will be no implications coming out of this diplomatic situation at all," Mattis said.

In earlier remarks at the start of their talks, Mattis pledged unity with longtime ally Australia in fighting Islamic extremists who seek to intimidate the West.

"We are united, as I said, in our resolve, even against an enemy that thinks by hurting us they can scare us," Mattis said. "Well, we don't scare."

The meeting, held annually, touched on a range of subjects including defeating the Islamic State, stabilizing Afghanistan and dealing with North Korea's nuclear threats.

Tillerson stressed the enduring U.S.-Australian alliance and said it will prevail in "this common fight we share against the most heinous of actions we've seen most recently in London yet again." He did not elaborate on the London attack.

Police say three men drove a van over London Bridge on Saturday and struck pedestrians before crashing the vehicle outside a pub. The attackers, wielding blades and knives, ran to a well-known fruit and vegetable market and there they stabbed people in several different restaurants. Seven people were killed and at least 48 were hospitalized. Police fired 50 bullets to stop the violence, killing the three attackers and wounding one member of the public.

In her opening remarks, Bishop said "countering terrorism" would be high on the meeting's agenda.

"The global terrorist threat is ever evolving, we've seen brutal attacks in a number of European cities, we've thwarted attacks here in Australia, and so we want to discuss with you, the links back into the Middle East, the role we're playing with you in Iraq and Syria and also Afghanistan," Bishop said. "We are united in our resolve to defeat ISIS, the Islamic State terrorist organization and its ilk."

Australian Defense Minister Marise Payne said her government is concerned by IS linkages in Asia and the Pacific.

"For Australia, from our perspective today it's important that we do discuss ISIS's links in Southeast Asia, violent extremist organizations and the risk that returning foreign fighters who may endeavor to resume positions in their own countries might pose in this region," Payne said. "They'll come back with battlefield skills, they'll come back with hardened ideology, they'll come back angry, frustrated, and we need to be very aware of that."