US President Donald Trump has expressed his determination to impose maximum pressure on Iran, including tightening sanctions.

Trump signed a presidential memorandum regarding Washington's planned policy on Iran on Tuesday.

The document directs government departments and agencies to toughen measures, such as restricting Tehran's nuclear program and blocking its support for Iran-linked armed forces in the Middle East.

Trump told reporters that he hopes the US will not have to use the measures "very much." He added, "We will see whether or not we can arrange or work out a deal with Iran."

The US president expressed a willingness to meet with his Iranian counterpart. He said what matters most is not to allow Iran to possess nuclear weapons.

During his first presidency, Trump resumed economic sanctions on Iran, raising fears that the two countries were headed toward a military confrontation.

In 2020, Trump ordered a US airstrike that killed a general of Iran's elite Islamic Revolutionary Guard Corps, who was revered as a hero in the country.

Trump told reporters on Tuesday that if Iran were to assassinate him, the country "would be obliterated." He added that he had left instructions.