Neither President Donald Trump nor any senior member of his administration have condemned the murder of Iranian nuclear Scientist Mohsen Fakhrizadeh by assassins likely working for Israel and probably abetted by the Trump administration.

Fakhrizadeh and other convoy members were killed in an attack in the city of Absard to the east of Tehran Friday. He died from his wounds at a hospital in the city. At least three of the attackers were killed by his bodyguards.

There is still no official comment on the murder from Trump, Israel's closest world ally but Iran's most implacable foe. However, Trump showed he approved of Fakhrizadeh's murder by retweeting an Israeli journalist, Yossi Melman, who called Fakhrizadeh's killing "a major psychological and professional blow for Iran."

Trump administration officials keep saying they're monitoring the situation and don't want to comment publicly to avoid further inflaming the explosive situation.

In contrast, both the United Nations and the European Union have already condemned Fakhrizadeh's assassination.

The UN condemned Fakhrizadeh's killing Saturday but urged at the same time to avoid an "escalation of tensions."

"We urge restraint and the need to avoid any actions that could lead to an escalation of tensions in the region," said a UN spokesman. "We condemn any assassination or extrajudicial killing."

The European Union called Fakhrizadeh's killing "a criminal act" that "runs counter to the principle of respect for human rights the EU stands for." It also urged all parties to show "calm and maximum restraint."

"In these uncertain times, it is more important than ever for all parties to remain calm and exercise maximum restraint to avoid escalation which cannot be in anyone's interest," said the EU statement.

On the other hand, Germany called for calm and said all sides should avoid taking any moves that lead to escalation.

"We call on all parties to avoid taking any action which could lead to a new escalation of the situation," which "we absolutely do not need at this moment," said a German foreign ministry spokesman.

There has been no claim of responsibility for Fakhrizadeh's murder, but Israel is probably behind this latest murder of a scientist associated with Iran's nuclear program.

Fakhrizadeh is the fifth Iranian nuclear scientist known to have been murdered by Israel since 2010. Four of these scientists were murdered by Israeli operatives from 2010 to 2012: Masoud Alimohammadi, Darioush Rezaeinejad and Mostafa, Ahmadi Roshan, and Majid Shahriari.

Shahriari and Roshan were blasted to death by bombs attached to their cars. Rezaeinejad was shot dead while a motorcycle-bomb killed Alimohammadi. Another scientist, Fereydoon Abbasim, was wounded in an attempted murder.

Fakhrizadeh's assassination is the second high-profile murder of a top Iranian official after IRGC Quds Force commander, General Qassem Soleimani, was murdered in Baghdad last January in a U.S. airstrike authorized by Trump.

Major General Mohammad Bagheri, Chief of Staff for the Armed Forces of the Islamic Republic of Iran, warned of "severe revenge" against those behind the assassination of Fakhrizadeh.