A select group congressional leaders received a classified briefing on Iran from the White House following complaints that lawmakers had not been kept informed on recent U.S. military moves in the Middle East.
The briefing was given on May 16 to the so-called Gang of Eight, a varying group of four Democratic and four Republican lawmakers who are at times given highly classified intelligence information.
Briefings are also scheduled to be given to the full Senate and House of Representatives next week, U.S. news media are reporting, citing sources.
Democratic Senator Mark Warner, the ranking member of the Intelligence Committee, did not comment following the Gang of Eight briefing, but he did say the administration should keep lawmakers better informed about any threat from Iran.
"I think obviously there are certain protections that have to be maintained for the Gang of Eight, but it's very important that more members hear this story," Warner told reporters.
House Speaker Nancy Pelosi, also a member of the Gang of Eight, said a failure to keep Congress informed is "part of a pattern" for the current administration "that is not right" because Congress alone has the power to declare war.
"So I hope that the president's advisers recognize that they have no authorization to go forward in any way" against Tehran, she said.
Amid growing tensions between the United States and Iran, Washington announced the deployment of an aircraft carrier battle group and a bomber task force to the Persian Gulf to counter what U.S. officials called "clear indications" of threats from Tehran to U.S. interests or its allies in the region.
U.S. officials have told their European allies that the recent military buildup is a "defensive" move, which is being made in response to multiple threats coming out of Iran.
Brian Hook, the U.S. special representative for Iran, told RFE/RL on May 14 that Washington was "just trying to restore deterrence."
"We're not spoiling for a fight,” Hook said.
Asked at the White House on May 16 whether rising tensions with Tehran could lead to war, President Donald Trump replied: "I hope not."
Mixed with his threatening language, Trump has recently made comments urging Iranian leaders to sit down for talks, and tweeted on May 16 he was "sure that Iran will want to talk soon.”
Some lawmakers accused the White House of attempting to provoke Iran into retaliating.
"The Iranians moving weapons around is not a new thing, and that they may be doing it at a more rapid pace after we have threatened them with a carrier strikes group is not surprising," said Democratic Representative Jim Himes, a senior member of the House Intelligence Committee.
Republican Senator Marco Rubio defended the White House's actions, saying there has been "a persistent and clear stream of information" about Iranian threats to U.S. troops and other assets in the Middle East.
Rubio, speaking on the Senate floor, said Iranian forces "and their proxies in the region pose a serious and potentially imminent threat to U.S. forces and U.S. civilians in Iraq and in the broader Middle East."
Trump has taken a hard line on Iran since he took office in January 2017.
In May 2018, he pulled the United States out of a 2015 nuclear deal that Iran signed with six world powers. The accord provided Tehran with relief from sanctions in return for curbs on its nuclear program.
In withdrawing, Trump said the terms were not tough enough to prevent Iran from developing nuclear weapons and did not address Iran's missile program or Tehran's alleged support for militants in the region.
Iran described the U.S. moves as "psychological warfare," and Foreign Minister Mohammad Javad Zarif has said there is "no possibility" of talks with the United States at this time.
Zarif also said Tehran was showing "maximum restraint" despite the U.S. withdrawal from the deal and accused Washington of an "unacceptable" escalation of the crisis.