The billionaire Hinduja brothers have been formally charged in a special court in connection with an arms bribery case in India.

The trial has been set for 4 December but observers say it may be delayed if the brothers appeal to a higher court.

Bofors gun deal sparked a scandal in India

British citizens Srichand and Gopichand Hinduja, and Prakash, who is Swiss, face allegations of criminal conspiracy, cheating and bribery relating to a major Indian arms deal in the 1980s.

The brothers control a global business empire which has made them one of Britain's wealthiest Asian families.

On Thursday, a judge in India said there was enough evidence against the Hindujas brothers for them to face trial .

At Thursday's hearing in Delhi, special judge Prem Kumar said there was "a prima facie case that the accused persons... are liable to be charged".

BBC correspondent Jill McGivering in Delhi says the verdict was an important step towards an actual trial.

Charges

The case dates back to the mid-1980s when the Indian Government finalised a deal with Swedish arms company Bofors for the supply of 400 field guns.

The Bofors affair

March 1986 Bofors and Indian Government sign arms contract April 1987 Allegations of bribery surface October 1999 First charges filed in the case October 2000 Hinduja brothers charged June 2002 Indian court drops charges against Hindujas

Allegations circulated in the media soon after that bribes had been paid, and Indian officials launched an investigation.

Prosecutors argue that about $8m was paid to the Hinduja brothers by Bofors at the time of the deal - the Hindujas strongly deny any wrongdoing.

The current charges came after a long investigation by Indian police which also implicated a number of top politicians, including the then prime minister, Rajiv Gandhi.

The brothers insist their decision to take British and Swiss nationality was not related to the criminal charges against them.

The issue of the Hindujas' nationality led to a political row in the UK, which resulted in the resignation of the Northern Ireland Secretary Peter Mandelson