US Secretary of State Mike Pompeo abruptly cancelled a scheduled trip to Germany, where he was planning to meet with Chancellor Angela Merkel "due to pressing issues," the State Department said early on Tuesday.

No specific reason was given for the cancellation. The press pool travelling with Pompeo has not been told where they are going next, and have been warned they may not be able to report from the country they are going to until after their departure.

“Unfortunately, we must reschedule the Berlin meetings due to pressing issues. We look forward to rescheduling this important set of meetings. The Secretary looks forward to being in Berlin soon,” State Department spokesperson Morgan Ortagus said, according to the press pool travelling with Pompeo.

The sudden schedule change comes two days after the Pentagon deployed a carrier and a bomber task force to the Middle East, in response to “specific and credible” intelligence that suggested Iranian forces and proxies were planning to target US forces in Syria, Iraq and at sea.

The carrier group has been ordered to Strait of Hormuz in order to send a deterrent message to Iran, US officials said on Sunday.

The move is likely to heighten tensions as Tehran explicitly warned the US in April against any moves to block or interfere with the Strait. The 21-mile-wide waterway separates Iran from other Gulf countries and is a crucial conduit for the global economy, with 30 percent of the world’s crude oil passing through it.

Pompeo said Sunday that the deployments have been in the works for “a little while” and that the US will “hold the Iranians accountable for attacks on American interests.”

There are few countries where press travelling with US officials are barred from reporting until after departure, with Iraq and Afghanistan being the most common.

As the Trump administration has ratcheted up its maximum pressure campaign on Iran, US officials and analysts have long flagged the possibility that Tehran will strike back, likely through proxies, at US troops, personnel and allies in the Middle East.

The secretary had been in the midst of an overseas trip and had been due to meet Tuesday with Merkel and German Foreign Minister Heiko Maas about “issues of mutual concern,” including Russia, China and Syria, according to the State Department.

Maas’ office said in a statement on Tuesday that he had spoken to Pompeo by phone and that the two “agreed to quickly find a new date for a meeting.”

The cancellation also comes amid news that President Donald Trump, who is urging caution among senior advisers about potential US military intervention in Venezuela, is growing frustrated that some aides are openly teasing military action in the country, where a battle for power has recently intensified.

Last week, Pompeo told Fox News that “military action is possible. If that’s what’s required, that’s what the United States will do.”

On his trip, Pompeo was set to travel to London, Rovaniemi, Finland, and Nuuk, Greenland, in addition to the now-cancelled stop in Berlin.