The United States and Britain announced widespread sanctions against Iran's military drone program on Thursday, in response to its weekend retaliatory attack against Israeli targets in occupied Palestine.

"Today, we are holding Iran accountable -- imposing new sanctions and export controls," US President Joe Biden said in a statement.

Washington's sanctions target 16 people and two companies reportedly involved in Iran's unmanned aerial vehicle (UAV) program, as well as components for the drones used in the Saturday attack, according to the Treasury Department.

Iran's representative to the United Nations, Amir Saeid Iravani, confirmed in mid-April that Iran's Operation True Promise came within the framework of self-defense and as permitted by international law, and only targeted military sites to avoid civilian targets, in contrast to the Israeli aggression that targeted the Iranian consulate in Syria.

He explained that the retaliatory attack came in "the exercise of Iran's inherent right to self-defense as outlined in Article 51 of the Charter of the United Nations and recognized by international law."

In coordination with the US Treasury, the UK government also announced sanctions against Tehran on Thursday, targeting seven individuals and six companies for allegedly enabling Iran to continue what it described as "destabilizing regional activity, including its direct attack on Israel."

British Prime Minister Rishi Sunak said the UK had sanctioned the "ringleaders of the Iranian military and forces responsible for the weekend's attack."

The announcement came following British Foreign Secretary David Cameron's arrival from a recent trip to "Israel" where he met with Israeli occupation Benjamin Netanyahu.

Alongside its sanctions against Iran's UAV program, the US also targeted five companies providing parts for Iran's steel industry, and an automaker allegedly involved in providing "material support" to Iran's Islamic Revolution Guard Corps (IRGC).

"Iran's metals sector generates the equivalent of several billion dollars in revenue annually, with the majority coming from steel exports," the Treasury Department said.

"We will continue to deploy our sanctions authority to counter Iran with further actions in the days and weeks ahead," US Treasury Secretary Janet Yellen confirmed in a statement.

Read more: 'Operation True Promise' impacts regional order: Bloomberg