India's Prime Minister has assured Theresa May he is "closely" following the case of a Scots ex-serviceman jailed in the country.

During almost three hours of talks in New Delhi, May told Narendra Modi the plight of the so-called Chennai Six was "a case of concern" in the UK.

Former paratrooper Billy Irving, from Connel near Oban, was among six men given five-year prison sentences earlier this year.

A court found they had entered Indian waters in 2013 without permission carrying unlicensed firearms.

British sources said Modi assured the May he was aware of UK concerns.

He pledged to consider whether or not there was anything that could be done by the two governments once the current appeal process has concluded.

The jailed men insist they were conducting legitimate anti-piracy work protecting merchant ships.

Their family and friends have conducted a high-profile campaign to lobby for them to be freed.

The UK Government has not taken any position on the allegations against the men and has made clear it respects the independence of the Indian judiciary.

Ministers have already raised the case around 40 times - including five times with Modi - but diplomatic action has focused on ensuring the matter is resolved as swiftly as possible.

Following Monday's talks, a UK source said: "The Prime Minister raised the case of the Chennai Six and said that this was a case of concern in the UK.

"Prime Minister Modi said that they were aware of our concerns and that they were following the case closely, that there was a process that now needs to run - given that it has gone to appeal - and that once that process is complete, we should look at whether there was more that could be done between the two governments."