A South Korean court on Friday granted bail to the two Indian sailors jailed in South Korea in December for their role in the country's worst oil spill.

"They have been given bail but they cannot come to India now," National Union of Seafarers of India general secretary Abdulgani Y Serang said.

Their bail is conditional and the matter is pending with the Supreme Court in Seoul, Serang said, adding that the legal proceedings might take some time.

Captain Jasprit Chawla and Shyam Chetan were found guilty after a crane barge collided with their crude carrier Hebei Spirit spilling oil in the sea.

The Korean upper court sentenced Chawla to 18 months in jail and Chetan got eight months on charges of negligence resulting in marine pollution.

The ruling sparked widespread anger in the international shipping community, which insisted the tanker crew were blameless. Indian seafarer unions also staged several protests.

The barge owned by Samsung Heavy Industries rammed the anchored 147,000-tonne supertanker Hebei Spirit. The ship was holed in three places and 10,900 tonne of crude oil was spilt, coating miles of beaches.

The appeal court found that Samsung was mainly to blame for the accident but also maintained that the tanker crew chiefs failed to act promptly to minimise the spillage.

Meanwhile, sources said no date has been fixed for the Supreme Court hearing.