The aircraft carrier USS John Stennis operated in the Persian Gulf twice during its recent deployment, for three weeks earlier this year and a week in early April.

“It’s something we’ve been working on for a little while,” Secretary of State Mike Pompeo told reporters traveling with him to Europe. “It is absolutely the case that we have seen escalatory actions from the Iranians, and it is equally the case that we will hold the Iranians accountable for attacks on American interests.”

Pompeo did not provide specifics on Iran’s potential actions, but said Iran “should understand about how we will respond to actions they may take” and that for any actions by related third-parties or proxies “we will hold the Iranian leadership directly accountable for that.”