The extension, brokered by the International Transport Workers Federation with ship owners and managers, came into effect on April 1 and is designed to protect sailors and vessels at risk of attack.
"It (the zone) is extended up to the Indian coast and we don't think that that is the right thing to do," Captain H.
Khatri, a deputy director-general of shipping at the Directorate General of Shipping in Mumbai, told AFP.
"There are no piracy incidents in these waters so it shouldn't be an issue," he added.
The extension provisions include increasing security on ships travelling in the area to reduce the risk of attacks and paying compensation to seafarers if their vessel is targeted or if they are injured or killed.
An agreed "high risk zone" with similar terms lies off the coast of Somalia, where an international force is patrolling to protect shipping in the busy maritime corridor.
India's opposition to the extension comes as the country's coastguard and navy are on high a