The International Criminal Court on Friday welcomed US President Joe Biden's lifting of sanctions imposed by Donald Trump on the tribunal's prosecutor, saying it signalled a new era of cooperation with Washington.

The Trump administration imposed financial sanctions and visa ban on Fatou Bensouda and another senior court official last year after she launched an investigation into alleged war crimes by US military personnel in Afghanistan.

The head of the group representing The Hague-based court's member countries expressed "deep appreciation" for the move, which comes as the Biden administration seeks a more cooperative approach on a dispute that has alienated allies.

"I welcome this decision which contributes to strengthening the work of the court and, more generally, to promoting a rules-based international order," Silvia Fernandez de Gurmendi, head of the Association of States Parties to the ICC, said in a statement.

Fernandez said the ICC had "always welcomed the participation" of the United States in achieving justice for war crimes, despite the fact that the US did not ratify its founding Rome Statute in 1998.

"I trust this decision signals the start of a new phase of our common undertaking to fight against impunity for these crimes," she added.

Fernandez said the US decision also came at a "fundamental juncture" when reforms were being enacted at the court, which has also come under scrutiny over internal matters including judges' salaries.

US Secretary of State Antony Blinken said as he announced the lifting of the sanctions that he was encouraged by the reforms.

However the new administration has continued to oppose the Afghan probe, as well as a separate investigation into alleged war crimes in the Palestinian territories by US ally Israel.

Gambian-born Bensouda is leaving her job in June and will be replaced by British human rights lawyer Karim Khan, who now can open his work without the burden of looming sanctions.