Republican senators are backing President Donald Trump’s pressure campaign on Iran while saying the U.S. needs to work with international partners and avoid miscalculations that could lead to unintended conflict.

Senate Majority Leader Mitch McConnell on Tuesday praised the administration’s plan to send 1,000 additional troops to the Middle East and placed blame for the risk of conflict on “Tehran’s decisions to resort to violence.” The Republican leader also spoke of the need for diplomacy and international cooperation in response to attacks on two tankers near the Strait of Hormuz last week, attributed to Iran.

“The president has said he does not seek conflict with Iran. Neither does the Senate,” McConnell said on the Senate floor. “The U.S. and our partners need to stand firm and apply concerted, coordinated, diplomatic and economic pressure until Tehran changes its behavior.”

The calibrated response shows Republicans supporting Trump’s foreign policy while urging solutions that could keep the U.S. out of an armed confrontation. Their warning against unilateral action also underscored the need for Trump to engage with the allies whose advice he ignored when he decided to pull out of the 2015 nuclear deal aimed at limiting Iran’s uranium enrichment.

“I support the president’s maximum pressure campaign,” Texas Senator John Cornyn told reporters. “What we need to do is get Europe to realize that Iran is not a trustworthy partner and that they will work with us to counter Iran’s efforts to get a nuclear weapon.”

Senate GOP Briefing

Senate Republicans will get a closed-door briefing Tuesday about the administration’s position from David Hale, the State Department’s undersecretary for political affairs. Senate Minority Leader Chuck Schumer told reporters that Democrats declined to hear from him, demanding instead that Trump personally explain the findings that led the administration to conclude Iran was behind last week’s attacks.

Schumer called Trump’s Iran policy “erratic and opaque.” He said Trump should take time from a rally this evening kicking off his 2020 presidential election to address the matter.

“I don’t know what their strategy is and it doesn’t seem consistent,” Schumer told reporters.

Democrats urged caution, especially regarding signals the U.S. is sending to Iran, a longtime adversary.

Maryland Senator Ben Cardin said U.S. troop movements could cause Iran to “make a miscalculation” and respond with force.

‘Pressure Cooker’

“There is a belief on both sides of the aisle that a military confrontation with Iran started by the U.S. would be a very, very bad idea,” Cardin said.

Senator Bob Menendez, the ranking Democrat on the Senate Foreign Relations Committee, said Congress is the only branch of government that can declare war and that any pre-emptive strike against Iran would have to be approved by the House and Senate.

“In the absence of a direct attack, any proactive action would be a declaration of war and I think that has to come before the Congress,” Menendez said. “Many of my colleagues -- on a bipartisan basis -- hold that view.”

Like Schumer, Menendez faulted the Trump administration for what he characterized as a dangerous strategy with no certain end goal and one that could backfire.

“If your maximum pressure campaign has no release, then you have a pressure cooker that explodes,” Menendez said. “There needs to be maximum diplomacy at this time, particularly with our allies, who are still very much engaged with Iran, to get them back to the table and get a negotiation underway.”