Norway's $2 trillion wealth fund, the world's largest, said on Monday it has divested from US group Caterpillar as well as five Israeli banking groups on ethics grounds.

The five banks are Hapoalim, Bank Leumi, Mizrahi Tefahot Bank, First International Bank of Israel and FIBI Holdings, the fund said.

The groups were excluded"due to an unacceptable risk that the companies contribute to serious violations of the rights of individuals in situations of war and conflict," said the fund, which is operated by Norway's central bank.

Caterpillar did not immediately respond to a request for comment.

The fund's ethics watchdog, called the Council on Ethics, said that "in the council's assessment, there is no doubt that Caterpillar's products are being used to commit extensive and systematic violations of international humanitarian law."

The violations were taking place both in Gaza and the West Bank, the council said, adding that "the company has also not implemented any measures to prevent such use."

"As deliveries of the relevant machinery to Israel are now set to resume, the Council considers there to be an unacceptable risk that Caterpillar is contributing to serious violations of individuals’ rights in war or conflict situations."

The Norwegian fund announced on August 18 it would divest from six companies as part of an ongoing ethics review over the war in Gaza and developments in the West Bank, but declined at the time to name any groups until the stakes were sold.

The fund's ethics watchdog, the Council on Ethics, had initially been scrutinizing Israeli banks' practice of underwriting Israeli settlers' housebuilding commitments in the region.

This is a developing story.