A senior U.S. Navy commander in Asia welcomed on Thursday an agreement by Japan and Australia to tighten military cooperation that will bolster the United States in a region where China's influence is growing.

Prime Minister Yoshihide Suga and Australian leader Scott Morrison on Tuesday agreed in principle on a Reciprocal Access Agreement (RAA) that will more closely align the allies through a legal framework allowing each other's troops to visit for training and to conduct joint military operations.

"That kind of agreement is really helpful and encouraging to everybody in the region. We are very supportive of that agreement and we look forward to exercising along right with them," Vice Admiral William Merz, commander of the U.S. Navy's Seventh Fleet, which is headquartered in Japan, said during a roundtable briefing.