India's Agriculture Minister Sharad Pawar said on Tuesday he had asked the prime minister to reverse a ban on cotton exports and complained that he had been kept in the dark about the move.

India, the world's second-largest producer of the fibre after China, unexpectedly announced an immediate ban on exports of the commodity Monday, saying it wanted to protect supplies for domestic mills.

The decision sent cotton prices soaring on New York's commodity markets and is expected to send buyers in China flocking to the US market for supplies.

"This is a very serious issue," Pawar told reporters, adding that he had written a letter to Prime Minister Manmohan Singh on the issue.

"I was kept in dark on the issue and have requested the prime minister for revocation of the ban as our production is higher this year and farmers are complaining of falling prices."

India already has exported 8.5 million bales in the fiscal year ending March 31, more than the government's target of 8.4 million bales.

The ban comes just six months after India completely freed cotton export controls. India had banned cotton exports in April 2010 and lifted the ban in the same year