Pakistan's cotton growers are angry at a decision by the Indian authorities to ban imports of their products.

The row over cotton threatens to add yet another dimension to the tensions between India and Pakistan.

Cotton is on a list of products that may be traded openly between the two nations - many other transactions take place illicitly via middlemen in third countries.

What has upset Pakistan's cotton growers is a letter received from the Agriculture Ministry in Delhi.

The letter says that no further imports of raw cotton from the Pakistan side of the border will be permitted to avoid the spread of diseases, described as virulent under Indian conditions.

Disease

The letter refers to the presence of seeds of uncertain origin, leaves and stalks in raw cotton from Pakistan.

Pakistani cotton growers say this is ridiculous as much of the crop in both countries comes from the border region of Punjab where conditions are identical on either side of the boundary that separates the two nations.

Maqbool Sethi, chairman of the Karachi Cotton Association also says there are no problem of disease.

"We think this is just a fabricated excuse to ban the import cotton from Pakistan," he says.

Suspicions

On the Pakistani side there are suspicions that in reality the ban has been imposed as the result of political tensions over Kashmir or after lobbying by Indian cotton growers keen to eliminate an emerging source of competition.

Cotton is vitally important to Pakistan's economy, and the Indian market is seen as offering huge potential for future export growth.

However, at present only about 3% of Pakistan's cotton goes to India.

So far there has been no further comment on the ban from the Indian authorities in Delhi.