Republican senators are insisting they need to review President Donald Trump's announced agreement with Iran before deciding whether it delivers on the administration's promise to prevent Tehran from obtaining a nuclear weapon.

Trump has promoted the preliminary agreement as a breakthrough that could end nearly four months of conflict, reopen the strategically vital Strait of Hormuz, lower energy prices, and stabilize the Middle East.

But many of his allies on Capitol Hill say they have not yet seen the text of the memorandum of understanding reportedly signed Sunday by Vice President JD Vance and Iranian officials.

"The MOU, I want to see it myself," Sen. Lindsey Graham, R-S.C., told reporters, according to The Hill.

Graham, one of the Senate's leading Iran hawks, said the agreement sounds promising when described by U.S. officials but concerning when characterized by Tehran.

He warned that any deal allowing Iran to continue enriching uranium would resemble former President Barack Obama's 2015 nuclear agreement, which Trump withdrew from during his first term.

Several Republican senators stressed that enforcement will be the key test.

Senate Majority Leader John Thune, R-S.D., acknowledged that lawmakers have not been fully briefed and said questions remain about compliance, verification mechanisms, and potential sanctions relief for Iran.

Sen. John Kennedy, R-La., echoed that skepticism, saying it remains "very difficult if not impossible to trust the Iranian government."

The administration has defended the agreement, circulating talking points to Republican lawmakers stating that "Iran will never have a nuclear weapon" and arguing that the framework is stronger than the Obama-era Joint Comprehensive Plan of Action.

Trump officials also point to falling energy prices and the planned reopening of the Strait of Hormuz as early signs of success.

The lack of public details, however, has fueled calls for congressional oversight.

Sen. James Lankford, R-Okla., argued that any lasting agreement involving Iran's nuclear program should receive congressional approval, Politico reported.

Graham similarly declared that lawmakers must have the opportunity to review and vote on a final deal.

Some Republicans are already praising Trump's diplomatic effort.

Sen. Rand Paul, R-Ky., welcomed negotiations as the best path to ending the conflict, while Sen. Josh Hawley, R-Mo., highlighted the potential economic benefits of reopening the Strait of Hormuz, including lower gas and fertilizer prices.