Kuwait has asked Japan to delay signing some parts of the drilling contract it has drawn up with Arabian Oil Co. of Japan, industry sources said Tuesday.

The request is expected to make it difficult for Arabian Oil to reach its goal of sealing the deal with the Kuwaiti government in early September. The company is trying to extend its rights to drill on the Kuwaiti side of the Khafji oil field. The rights are set to expire in January 2003.

The sources said Kuwait has been reluctant to promise Japan a steady supply of crude oil, which is one of the Japanese side's main conditions. It has also requested that the contract's duration be shortened to no more than five years, instead of the 10 to 20 years being sought by Japan.