WASHINGTON — Tensions flared behind closed doors Wednesday as defense and intelligence officials briefed some lawmakers about the war in Iran, with Republicans and Democrats expressing frustration about a lack of clarity and information about President Donald Trump’s strategy, according to four congressional officials who attended the briefing and a lawmaker who was briefed on it later.

Much of the frustration during the briefing for the House Armed Services Committee centered on the prospect of the United States’ sending ground troops into Iran, the officials and lawmaker said, including what the troops could be used for and whether the U.S. can adequately protect them once they were deployed.

“There was no plan, no strategy, no end game shared, and they didn’t give any answers. It’s unclear if there isn’t a plan or if there is a plan and they wouldn’t share it with members,” one of the congressional officials said.

The briefing took place as the war nears the one-month mark and the Trump administration is both engaging in a diplomatic effort to try to end it and sending more troops to the Middle East while Trump weighs whether to deploy American forces on the ground inside Iran.

The chairman of the Armed Services Committee, Rep. Mike Rogers, R-Ala., acknowledged in a text message to NBC News after the briefing that there has been some frustration with “ALL the briefings that we have been receiving for the last several months.”

He said that “criticism has NOTHING to do with Operation Epic Fury.”

“I fully support what the administration is doing in Iran,” he wrote. “But, when briefing members they need to be prepared to deliver substantive information and more fully answer questions.”

Rep. Nancy Mace, R-S.C., criticized the briefing afterward, writing on X: “Just walked out of a House Armed Services Briefing on Iran. Let me repeat: I will not support troops on the ground in Iran, even more so after this briefing.”

The Defense Department and the White House did not immediately respond to requests for comment Wednesday night.

The congressional officials said the briefers could not provide details about the possibility of deploying U.S. troops to Iran but would not rule it out. And some lawmakers who attended the briefing made it clear in the closed-door meeting that they would not support boots on the ground, the officials said.

The lawmaker who was briefed on the contents of the briefing said a “red line” for some lawmakers who currently support the war would be U.S. ground troops in Iran.

“That’s the time that they’re going to abandon the effort. There was concern that that is not being ruled out,” the lawmaker said.

The four congressional officials in the briefing also said there was frustration with the defense and intelligence officials over what they view as a lack of a cohesive strategy for the war, specifically where it is heading. They also said tensions flared over conflicting explanations from the administration about the justification for starting the war.

The briefers said the additional U.S. troops headed to the region are intended to give Trump options, the congressional officials said.