WASHINGTON: The US has unveiled new steps to fight terrorism and add muscle to the Trump administration's ability to pursue terror suspects, their financiers and supporters worldwide.

Utilising a new executive order signed by President Donald Trump, issued on the eve of the 9/11 anniversary, the Treasury Department sanctioned over two dozen individuals and entities from 11 terrorist groups, including Pakistan-based Tehrik-e-Taliban Pakistan (TTP).

Noor Wali, also known as Mufti Noor Wali Mehsud, from the TTP was one of the sanctioned individuals, the US State Department said, describing him as a Specially Designated Global Terrorist.

He was named the leader of the terror group in June 2018 following the death of former TTP leader Mullah Fazlullah.

Under Noor Wali's leadership, TTP has claimed responsibility for numerous deadly terrorist attacks across Pakistan, the State Department said in a press release.

The executive order allows the US government to better target terror group leaders and provides new tools to pursue individuals who participate in terrorist training, Treasury Secretary Steven Mnuchin said.

It order also authorises secondary sanctions on foreign financial institutions that have knowingly conducted or facilitated significant transactions with sanctioned persons, Mnuchin said. He added that the order targets those actors for and behalf of specially-designated global terrorists.

"Specifically, we have leaders, operative and financiers from over 11 terrorist organisations, including Iran's Quds Forces, Hamas, ISIS, al-Qaida, and their affiliates," Mnuchin told White House reporters at a joint news conference with the Secretary of State Mike Pompeo.

Pompeo described the executive order as the "most-significant update" to counterterrorism sanctions authority since September 2001.

The treasury secretary said that his department was enhancing efforts to deny terrorists access to the financial system.

"Since the horrific attacks of 9/11, the US government has refocused its counter terrorism efforts to constantly adapt to emerging threats. President Trump's modernised counter terrorism Executive Order enhances the authorities we use to target the finances of terror groups and their leaders to ensure they are as robust as possible," Mnuchin said.

"These new authorities will allow the US Government to starve terrorists of resources they need to attack the United States and our allies, and will hold foreign financial institutions who continue to do business with them accountable.

"These new tools aid America's unrelenting efforts to cut off terrorists from their sources of support and deprive them of the funds required to carry out their destructive activities. They serve as a powerful deterrent to radical terror groups and those seeking to aid their nefarious goals," the treasury secretary said.

According to Pompeo, the new order amends the previous one by adding clauses that allow the departments of state and treasury to directly target leaders of terrorist groups and their associated entities without having to tie terrorist leaders to specific acts.

"Second, it more effectively and efficiently targets individuals and entities who participate in terrorist training and provides new authorities to impose sanctions on foreign financial institutions that knowingly do business with terrorists," Pompeo said.

"As these actions show, today's executive order by President Trump adds further muscle to the US counter terrorism efforts," the secretary of state said.

"It will help us to ensure that the deadly attacks of September 11 that occurred 18 years ago this week are never repeated on American soil. Never," he said.