Settling all the outstanding land restitution claims lodged during the first land claims window period will cost an estimated R16.9-billion, Rural Development and Land Reform Minister Gugile Nkwinti said on Friday.

In a written reply to a parliamentary question, he said not all outstanding claims had been researched to determine the exact extent of the properties and rights under claim, and for this reason a definitive cost could not be provided.

However, the National Treasury had conducted an expenditure and performance review of the restitution programme, based on the number of claims outstanding as at March 31 last year.

"At that stage, it was estimated that an amount of R16.9-billion will be required for these claims," he said.

Last year, President Jacob Zuma announced that a second land claims window period would be opened for those who missed the previous closing date -- December 31, 1998.

The second window is for a period of five years, and ends in June 2019.