Angus Robertson Share this specific contribution Share a link to this specific contribution: Share contribution 1 on Twitter Share contribution 1 on Facebook Share contribution 1 via Email Copy link to contribution 1 to clipboard Copy link To ask the Secretary of State for Defence in which country the gas reservoirs for Trident nuclear warheads are filled with tritium; and if he will make a statement. (303891) Mr. Bob Ainsworth Share this specific contribution Share a link to this specific contribution: Share contribution 2 on Twitter Share contribution 2 on Facebook Share contribution 2 via Email Copy link to contribution 2 to clipboard Copy link [holding answer 3 December 2009]: This information is being withheld for the purpose of safeguarding national security.