A flight from London to Madrid could cost £5 more, while a trip to New York would rise by almost £30

Air passengers face having a carbon charge added to the price of tickets automatically under government plans to cut greenhouse gas emissions.

Ministers are considering measures that would require all airlines to introduce carbon offsetting payments at the point of ticket sale.

Payments would be voluntary but could work on an “opt-out” system. Similar measures could also be applied to trains, buses and ferries.

A flight between London and New York could increase by just under £30, falling to half that when travelling with the most fuel-efficient airlines. A journey between London and Madrid could rise by an estimated £5.

The plan was outlined as part of proposed reforms to raise public awareness of the carbon emissions released by different modes of transport while increasing