Under the offer, passengers will get 10 to 13 percent discounts in economy class to fly to Kolkata.

"We are the only carrier offering first class to Kolkata. But even so we offer additional discounts in the first class as well as business class fares to Kolkata to the tune of 5 to 10 percent," said AK Mitra, manager Air India, Bangladesh, at a press conference in Dhaka.

For the New Delhi flights, the airline also offers 5 to 10 percent discounts in first class and business class, he said. Economy class passengers will also get discounts, he added.

Air India also offers a promotional scheme titled Companion Free Scheme (CFS). Under the scheme, first class passengers of Dhaka-London-Dhaka can take a companion along for a surcharge of 25 percent and business class passengers can take a companion along for no additional cost except the applicable taxes.

Under the companion free scheme, the one-way fare for first class passengers is $1179 and returned fare is $2353 per passenger. The one-way fare for business class passenger is $683 and return is $1366.

The airline has also decided to increase its passenger capacity in its all flights operated from Bangladesh, Mitra said. The capacity will be increased to 292 from 272 in April, he added.

VA Sarika, airport manager, and A K Roy, assistant account manager of Air India, were present at the press conference.