Billions of pounds worth of British gold is hidden in the wrecks of merchant ships sunk during the First and Second World Wars, a team of experts believe.

Four research groups have spent 25 years producing a database tracking the gold shipped by the British Government to pay for munitions and goods during both World Wars.

Of the 7,500 merchant ships sunk, the teams have identified more than 700 which they believe may have been carrying vast quantities of gold and other precious metals.