Relatives of a group of former British soldiers, including two from Yorkshire, who were jailed in India are planning to deliver a 100,000-strong petition to Downing Street urging the UK Government to intervene.
Supporters including families of the six men are planning to hand over the petition urging Prime Minister David Cameron to step in to help their loved ones be released.
Billy Irving, from Connel, Scotland; Nick Dunn, from Ashington, Northumberland; Ray Tindall from Chester; Paul Towers, from Yorkshire; John Armstrong from Wigton, Cumbria; and Nicholas Simpson, from Catterick, North Yorkshire, were arrested on October 12 and have been in prison in India since October 24.
The men were working for US private maritime company AdvanFort providing anti-piracy protection when their ship was detained.
According to the men, Indian authorities claim the vessel entered Indian waters illegally with weapons on board, despite AdvanFort apparently insisting the ship had the correct papers.
They were granted bail in December but after objections from Indian officials, are yet to be released.
A further bail hearing is due to take place today, and the petition, set up on online platform Change.org, calls for the men to be released and also for the UK Government to act as guarantors.
According to relatives, an Indian security adviser has said that if the British Government were to provide assurances, the men would most likely be released.
The petition will be delivered to Downing Street by relatives including Mr Irving's girlfriend Yvonne MacHugh next week.
They had originally planned to deliver it on Thursday but are waiting for imminent news on the men's situation.
Ms MacHugh, 25, from Connel in north west Scotland, said: "I've just returned from India after what was the hardest and most emotional trip I have ever had to make.
"The men had lost a lot of weight, they looked exhausted and had lost hope of ever being released, their morale is at an all-time low.
"With very little communication from lawyers and the company, they have no idea what is going on with their case and I feel they're being scapegoated.
"We have now heard from a security official in India that if the UK Government gives these men surety, they will be released and allowed home.
"It is in our Government's hands to bring back these men who have fought for us as soldiers and now need the help of their country."
A spokesman for the Foreign Office said: "This is a difficult and important case, which the Prime Minister has raised with Indian ministers, as has the Foreign Secretary.
"We will continue to do all that we can.
"Consular staff continue to provide full assistance to all those British nationals detained. They are visiting regularly.
"While we are unable to demand the release of British nationals, or interfere in another country's legal processes, we continue to make very clear our interest in this case, and the importance of ensuring that it is resolved as quickly as possible."