The United States and Sudan on Wednesday signed the "Abraham Accords" under which the mainly Arab Muslim country agreed to normalise ties with Israel, the US embassy in Khartoum said.

"We congratulate the civilian-led transitional government on its signature today of the Abraham Accords Declaration, which will help further Sudan on its transformative path to stability, security, and economic opportunity," the embassy said on Twitter.

"The agreement allows Sudan, Israel and other signers of the Abraham Accords to build mutual trust and increase cooperation in the region."

The signing came during an unprecedented visit to Sudan by US Treasury Secretary Steven Mnuchin less than a month after Washington removed Khartoum from its blacklist as state sponsors of terrorism.

In October, Sudan agreed to the normalisation deal with Israel but said it would only come into force after its approval by a yet-to-be-formed parliament.

During the signing ceremony, Sudan's justice minister Nasr Abdelbari hailed the agreement as an "important step".

"It confirms our belief that peace strengthens relations and interests between people," he said in a video broadcast by state-run SUNA news agency.

Wednesday's signing made Sudan the third Arab country to ink the "Abraham Accords" after the United Arab Emirates and Bahrain last year.

Morocco has agreed a "normalisation" with Israel that restores past relations.