South Africa's former archbishop, Desmond Tutu, has backed compensation claims filed by apartheid victims.
Mr Tutu has broken with the government over the issue
Mr Tutu, who chaired South Africa's Truth and Reconciliation Commission, made a legal submission in support of the New York lawsuit.
"The obtaining of compensation for victims of apartheid... could promote reconciliation," he reportedly said.
By backing the suit against a number of international businesses, Mr Tutu has broken with ANC government policy.
The government of South African President Thabo Mbeki has opposed lawsuits against firms that did business with the apartheid government prior to its fall a decade ago.
Correspondents say Mr Mbeki's government is concerned that such lawsuits could undermine the reconciliation process - and scare off potential investors.
The lawsuit filed in New York names as defendants such companies as IBM, DaimlerChrysler, ExxonMobil and banks ranging from JP Morgan Chase to Deutsche Bank, Credit Suisse and Credit Lyonnais.
Judge John Sprizzo heard arguments in November and is expected to rule this month as to whether or not the case can go forward.
The South African Justice Minister, Penuell Maduna, asked the court last year to dismiss the case.
Government spokesman Joel Netshitenzhe said Mr Tutu did not understand the government position on the issue.
"This is that not settling the matter inside South Africa has profound implications for the future of the country, for instance... investment and job creation," he told the Sunday Independent of Johannesburg.
Mr Tutu's Truth and Reconciliation Commission identified about 22,000 people who were entitled to reparation payments of about $4,200 each.
South African media reported in December that nearly 4,000 of them had not yet received their payments.