Mumbai, June 26 -- The Great British pound is gaining momentum towards a four year high against the dollar fuelled by sharp sell-off in the greenback. The dollar index plunged under 97 mark on Thursday, its lowest level in more than three years amid easing geopolitical tensions and expectations of Federal Reserve rate cuts. US President Trump mediated ceasefire between Israel and Iran reduced safe haven appeal for the greenback. Meanwhile, sentiments for the dollar weakened after United States (US) President Donald Trump reiterated attacks on Federal Reserve's (Fed) independence, following Chair Jerome Powell's commitment to a "wait and see" approach on interest rates in the two-day semi-annual testimony before Senate. The US Dollar Index...