Story highlights Sen. John McCain told U.S. allies to watch what Trump does, not what he says, and praised the White House national security team in an interview Sunday

McCain also called for increased military spending, and sounded hesitant to embrace the Trump tax plan outlined last week

(CNN) Sen. John McCain has a message for US allies confused by the mixed messages and miscommunications coming from the White House on foreign policy: "Sometimes it's important to watch what the President does rather than what he says."

McCain was asked on CNN's "State of the Union" Sunday what he tells world leaders when President Donald Trump and his administration aren't on the same page -- as happened when the President declared in early April that an aircraft carrier strike group was headed to South Korea only for it to be revealed days later that the naval group was not on its way there after all.

"I tell them that [Trump is] surrounding himself with an outstanding national security team," McCain told anchor Jake Tapper, echoing his past praise for Secretary of Defense James Mattis and national security adviser H.R. McMaster. "I can't guarantee to world leaders that he will always listen to them, but he has so far."

The latest example of Trump's White House sending mixed messages to allies that prompted the line of questioning: On Saturday night, McMaster spoke to the South Korean director of national security, Kim Kwan-jin, to reaffirm that the US would cover the cost of an antiballistic missile system, the theater high-altitude air defense system, recently deployed to the country. But the remarks came after Trump told Reuters in an interview that he wanted Seoul to pay for it.

McMaster explained in a separate interview on "Fox News Sunday" that Trump meant the statements in a general way, in line with US public expectations on burden-sharing with allies.

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