Britain's Prime Minister David Cameron (C) poses inside the premises of the holy Sikh shrine the Golden temple in the northern Indian city of Amritsar February 20, 2013. REUTERS/Stringer

AMRITSAR, India - British Prime Minister David Cameron says a giant diamond his country forced India to hand over in the colonial era that was set in the late Queen Elizabeth I’s crown will not be returned.

Speaking on the third and final day of a visit to India aimed at drumming up trade and investment, Cameron ruled out handing back the 105-carat Koh-i-Noor diamond, now on display in the Tower of London.

One of the world’s largest diamonds, some Indians - including independence leader Mahatma Gandhi’s grandson - have demanded its return to atone for Britain’s colonial past.

“I don’t think that’s the right approach,” Cameron told reporters on Wednesday after becoming the first serving British prime minister to voice regret about one of the bloodiest episodes in colonial India, a massacre of unarmed civilians in the city of Amritsar in 1919.