MADRID (AP) — Spain's decision to remove a frigate on training exercises from a U.S. combat fleet that is approaching the Persian Gulf was taken purely for "technical reasons," the country's defense minister said Tuesday.

Margarita Robles insisted the decision was "not an expression of distaste" over the crossing into the Strait of Hormuz by the fleet headed by the USS Abraham Lincoln aircraft carrier.

The U.S. fleet is heading to the Persian Gulf at a time of heightened tensions between Washington and Tehran.

Robles insisted Spain's decision was "prudent" and "perfectly admissible" under the terms of a two-year cooperation agreement that placed the Méndez Núñez frigate with the U.S. fleet for advanced training. The ship and its 215 people on board have headed to Mumbai, India, she added.

"The United States government has embarked on a mission that wasn't scheduled when the agreement was signed," Robles told reporters during an official trip to Brussels.

She said Spain had never given its blessing for the frigate to go on a mission in the Persian Gulf and that it will return to the U.S. fleet once scheduled operations resume.

She declined to comment over the U.S.'s hard-line policy toward Iran but said Spain remains a reliable and committed member of NATO.