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March 15 (Reuters) - Scottish Mortgage Investment Trust , Britain's largest investment trust, will buy back shares worth 1 billion pounds ($1.27 billion) over the next two years, it said on Friday, as its portfolio companies deliver strong operational results.

SMT, one of asset manager Baillie Gifford's flagship trusts and an investor in big U.S. tech stocks, said the buybacks were part of its intention to take more "concerted action" to address the discount to net asset value at which the its shares trade.

Last year, the trust named Justin Dowley its new chair as part of a broader boardroom shake-up, as it sought to draw a line under a board dispute following a steep decline in its share price. ($1 = 0.7848 pounds) (Reporting by Eva Mathews in Bengaluru; Editing by Savio D'Souza and Rashmi Aich)