About 80 percent of the total seat capacity of Indian carriers, as per the bilateral air service agreement with 109 countries, were lying unutilised in 2010-11.

"India has bilateral air service agreement (ASA) with 109 countries and Indian carriers have utilised 20 percent of the total entitlement in the year 2010-11," Civil Aviation Minister Vayalar Ravi said in reply to a question in Lok Sabha today.

In the last three years, India has signed ASA with 15 new countries, which include Bhutan, Azerbijan, Kenya, Barbados, Bosnia and Herzegovina, Iceland, Iran, Nepal, Rwanda, Senegal, South Africa, Zimbabwe, Indonesia and Brazil.

Ravi said that Indian carriers were eligible to operate to foreign destinations according to respective bilateral ASA.

"However, actual operations by any airline is always guided by its commercial judgement," he added.

There were reports that Air India's first right to fly overseas was hampering the plans of private airlines to fly on more overseas routes.

As the existing law, Air India also has the first right to refusal on overseas routes as it is the national carrier.

The private airlines also allege that there were several routes on which Air India was not flying and also not giving up its rights to allow other airlines to operate.

As a result, the expansion plans of private sector airlines to destinations such as Dubai, Singapore, Thailand and the CIS countries were getting blocked.

The Comptroller of Auditor General (CAG) in its recent report had also blamed the Ministry of Civil Aviation for being liberal in exchange of bilaterals.