The deployment of a Navy carrier strike group – along with a bomber task force – designed to offset what the national security adviser said Sunday was a new threat from Iran had been previously planned, the Navy's top officer said Monday.

"The Abraham Lincoln Strike Group was planned to deploy for some time now," Chief of Naval Operations Navy Adm. John Richardson said at the annual Sea Air Space conference taking place just outside Washington this week.

Richardson described the deployment of the Lincoln, along with its support ships and tactical aircraft aboard the carrier, which were previously staged to participate in operations in Europe, as "a dynamic force deployment."

"They're designed to move around the globe very fuildly in response to changing security situations," he said, "if the dynamic changes and national leadership requires or requests that force package to go to a different theater."

National security adviser John Bolton announced the deployment of the strike group Sunday night as well as a separate bomber task force to the Middle East "to send a clear and unmistakable message to the Iranian regime that any attack on the United States interests or on those of our allies will be met with unrelenting force."

In a statement, Bolton described "a number of troubling and escalatory indications and warnings" by regime in Tehran and its proxy forces in the region, but did not offer any specifics.

When asked by a reporter for specifics about the security situation on Monday, Richardson deferred to Bolton's remarks. In a tweet following his formal remarks, Richardson clarified that the decision to move the Lincoln into the region came at the direction of Bolton and the secretary of defense.

The Photos You Should See – April 2019 View All 57 Images

The deployment comes at a time of high tension between the Iranian regime and the Trump administration. The White House took the unprecedented step of designating the Islamic Revolutionary Guard Corps a terrorist group last month, and Tehran responded with a similar designation for all U.S. forces operating in the Middle East.

More recently, the Trump administration began reenforcing sanctions on partner countries and other world powers that had begun purchasing Iranian oil as a part of the 2015 nuclear deal brokered by the Obama administration. The White House has indicated it wishes to dismantle that agreement. Foreign ministers representing the U.K., France, Germany and the EU took the unusual step over the weekend of publicly criticizing the U.S. decision "with regret and concern," noting that Tehran continues to abide by the terms of the deal.

Bolton is among the most hawkish members of Trump's Cabinet with regard to Iran.