Former ambassadors, members of Congress and representatives to international organisations said the US should revert to the policy imposed by former president Donald Trump in 2018, saying it was the only effective way to halt the expansion of Iran’s nuclear programme.
“Today, we write to urge you and your team to stop all diplomatic overtures toward the Islamic Republic of Iran and instead reimpose the 'maximum pressure' campaign — the only effective policy to protect the American people, the Iranian people, and others in the region and around the world from the Islamic Republic’s threats,” the former diplomats wrote.
“It was a campaign of isolation — diplomatic and economic — that worked in putting the regime on its heels, reining in its malign activities across the region and restoring America’s deterrent against it.”
The letter comes on the fifth anniversary of Mr Trump’s decision to withdraw the US from the Joint Comprehensive Plan of Action, a deal signed by Iran and world powers in 2015 that put limits on Tehran's nuclear programme in return for sanctions relief.
After the US withdrawal, Iran ratcheted up its nuclear programme, with a Pentagon official saying in March that Tehran had made “remarkable” progress in production since 2018 and could develop a bomb within 12 days.
Iran has long maintained that its nuclear programme is intended for peaceful purposes.
Most in Washington remain unconvinced, however, especially given Iran's activities in the region, which have frequently been described as “destabilising”.
In recent weeks, Iran seized two oil tankers in Gulf waters in the latest regional incidents.
And last week, the Biden administration announced new sanctions against the intelligence wing of the Islamic Revolutionary Guard Corps over its role in the detention of Americans Siamak Namazi, Emad Shargi and Morad Tahbaz, who have been held for years on what the US State Department calls “bogus” espionage charges.
Mr Biden, who took office in 2021, has long pushed for a return to the nuclear deal.
But that approach, the former officials wrote in Monday's letter, is “misplaced and reckless”.
“The United States should never pre-emptively set the negotiating table with concessions, not least with an adversary with four decades of rhetoric and actions targeting the United States and the American people,” they wrote.
“The approach of pre-emptively offering sanctions relief and that trust in the regime is entirely misplaced and reckless given the regime’s record of lying about its nuclear programme.”