European Union foreign policy chief Javier Solana on Saturday pledged "support and solidarity" for Britain over the capture of 15 sailors and marines by Iran, and said the incident must not complicate a push to impose further sanctions on Iran because of its disputed nuclear program.

"We are doing our utmost in cooperation with the British authorities," Solana told journalists at an EU summit in Berlin. "They have our support and solidarity."

Solana said a second U.N. Security Council resolution imposing sanctions over Iran's refusal to halt its program to enrich uranium would go ahead regardless.

"The resolution will follow its course," he said. "It will probably be approved today New York time or tomorrow. It would be a tremendous mistake if these two things were mixed."

The approach to the resolution is "not going to change because of the events of the last days. Nobody wants to change that, not even the British government."

Iran says its uranium enrichment program is aimed at peaceful uses such as producing electricity, while the United States says it is aimed at producing nuclear weapons.

Germany, which holds the rotating European Union presidency, said Saturday it would demand the immediate release of 15 British naval personnel captured at gunpoint by Iran's hardline Revolutionary Guards.

German Foreign Minister Frank-Walter Steinmeier told reporters the EU would "make clear we want an immediate liberation" of the British soldiers held by Iran.

The Foreign Ministry in Tehran insisted the Britons had been in Iranian waters and would be held for further investigations.