US President Donald Trump’s order to assassinate Iranian Major General Qassem Soleimani has prompted swift condemnation from several US officials and lawmakers in Congress.

Former US Vice President and 2020 Democratic presidential candidate Joe Biden warned that Iran will surely respond.

President Trump just tossed a stick of dynamite into a tinderbox, and he owes the American people an explanation of the strategy and plan to keep safe our troops and embassy personnel, our people and our interest, both here at home and abroad, and our partners throughout the region and beyond, Biden said on Twitter.

US Democratic leaders in both chambers of Congress expressed outrage over Trump’s ordered strike, saying the Republican president did not obtain congressional approval.

We cannot put the lives of American servicemembers, diplomats and others further at risk by engaging in provocative and disproportionate actions, said US House of Representatives Speaker Nancy Pelosi.

Tonight’s airstrike risks provoking further dangerous escalation of violence. America - and the world - cannot afford to have tensions escalate to the point of no return, Pelosi said in a statement.

The Administration has conducted tonight’s strikes in Iraq targeting high-level Iranian military officials and killing Iranian Quds Force Commander Qassem Soleimani without an Authorization for Use of Military Force (AUMF) against Iran. Further, this action was taken without the consultation of the Congress, she added.

US Representative Adam Schiff, another top Democrat in the lower chamber of Congress, warned Trump over the killing, saying Congress didn’t authorize and American people don’t want a war with Iran.

All steps must now be taken to protect our forces against the almost inevitable escalation and increased risk, Schiff tweeted.

Representative Ilhan Omar, a Muslim lawmaker from Minnesota and a fierce critic of Trump, also attacked the president for his order to kill the top Iranian general.

So what if Trump wants war, knows this leads to war and needs the distraction? Real question is, will those with congressional authority step in and stop him? I know I will, she tweeted.

US Senator and Democratic presidential candidate Elizabeth Warren called the American attack a reckless move that increases the likelihood of more deaths and new Middle East conflict.

Senator Tom Udall said the strike could put US forces and citizens in danger and very possibly sinking us into another disastrous war in the Middle East that the American people are not asking for and do not support.

I urge members of Congress on both sides of the aisle to show courage on this issue, and I urge the Trump administration to change course and pursue diplomacy before we are entangled in yet another war in the Middle East with no end in sight, he added in a statement.

Democratic Senator Ed Markey said: Trump’s apparent assassination of Soleimani is a massive, deliberate, and dangerous escalation of conflict with Iran. The President just put the lives of every person in the region - US service members and civilians - at immediate risk. We need de-escalation now.

Representative Eliot Engel, a Democrat from New York and Chairman of the House Committee on Foreign Affairs, said in a statement that we are now again on the brink of direct confrontation in the Middle East. Tonight’s action represents a massive escalation in our conflict with Iran with unpredictable consequences.

Finally, this strike went forward with no notification or consultation with Congress. To push ahead with an action of this gravity without involving Congress raises serious legal problems and is an affront to Congress’s powers as a coequal branch of government, he added.

The UN special rapporteur on extrajudicial executions, Agnes Callamard, also condemned the killing of Soleimani.

The targeted killings of Qasem Soleiman and Abu Mahdi Al-Muhandis are most lokely unlawful and violate international human rights law: Outside the context of active hostilities, the use of drones or other means for targeted killing is almost never likely to be legal, she wrote on Twitter.

Soleimani, the commander of the Quds Force of Iran’s Islamic Revolution Guards Corps (IRGC), and Abu Mahdi al-Muhandis, the second-in-command of Iraq’s Popular Mobilization Units (PMU), were killed in US airstrikes in the Iraqi capital Baghdad early on Friday.

The IRGC confirmed in a statement that Soleimani and al-Muhandis were martyred in the attack carried out by US helicopters. The Iraqi pro-government group also confirmed the incident.

The US Defense Department confirmed the strike, saying it came at the direction of the president.

The Iranian general was a globally famous defense strategist who played a key role in the counter-terrorism operations that led to the collapse of the Daesh terror group in Iraq and Syria.

Soleimani had survived several assassination attempts against him by Western, Israeli and Arab agencies over the past years. In November 2018, The New York Times revealed a March 2017 meeting in Riyadh to assassinate Iranian officials, namely Soleimani.

Tensions between Washington and Tehran have been rising ever since Trump in 2018 withdrew the US from the nuclear deal that Tehran had signed in 2015 with the US and five other nations.

Trump’s policy on Iran has been defined by military threats and economic sanctions. He adopted a hostile approach from day one. However, the so-called maximum pressure campaign has only backfired.