US House of Representatives' Speaker Nancy Pelosi on Thursday called for the United States to de-escalate tensions with Iran, after top lawmakers attended a White House briefing on the downing of an American drone by Tehran. 'It is essential that we remain fully engaged with our allies, recognize that we are not dealing with a responsible adversary and do everything in our power to de-escalate,' Pelosi, the top Democrat in Congress, said in a statement. 'This is a dangerous, high-tension situation that requires a strong, smart and strategic, not reckless, approach,' she added.