British Prime Minister David Cameron has asked Cabinet Secretary Jeremy Heywood to conduct an "urgent" investigation after documents declassified under the 30-year rule suggested a British special forces officer advised India on carrying out the attack.
Another confidential document that has become public is a letter from the office of the then British Foreign Secretary Sir Geoffrey Howe to the office of Prime Minister Margaret Thatcher on the meagre contribution of Indian High Commissioner Dr Seyid Muhammad to Indo-British ties.
"Although Dr Muhammad's contribution to the development of Indo-British relations has been limited (and somewhat overshadowed by the private efforts of Mr Swraj Paul), relations with India during his time in London have been excellent," Ricketts wrote.
Asked about the letter, Lord Swraj Paul, who was close to Indian Prime Minister Indira Gandhi, chuckled and said, "What can I say? I did my best to cement bilateral ties.
