"On this visit alone more than one billion pounds of business deals will be signed. And there's much more we can do," May told reporters after meeting with Indian Prime Minister Narendra Modi.

"We have also agreed to establish structural talks at officials level to identify what more we can do now before Britain leaves the EU to remove barriers to trade and investment." 

While the benefits of a deal to Britain are evident, sealing one will be no easy task in a country which has been negotiating with the EU as a whole on a free trade agreement for the best part of a decade.

India still has a rigorous regime of tariffs and red tape which have traditionally made it one of the most complex places to do business, even if the potential market is huge.

Britain's need to cut deals quickly once it leaves the EU gives Modi's government added bargaining power.

The Hindustan Times wrote on Monday with Britain's looming departure from the EU, "the UK needs trade with India more than ever".