after two weeks of difficult negotiations, a final declaration of the cop-26 conference in glasgow came down to a single word. but that one word, a compromise on coal usage was enough to get india s support and the deal was done. the british official presiding over the conference apologized for the last-minute change, but said it was important to keep the fragile climate agreement al alive. may i just say for all delegates, i apologize for the way this process has unfolded and i m deeply sorry. i also the deep disappointment, but i think as you have noted, it s also vital that we protect this package. [ applause ] the document reaffirms the importance of holding global warming to 1.5 degrees celsius. it requests that countries be more aggressive about their emissions targets at next year s conference in egypt, and as we mentioned, it agrees to phase down the use of coal instead of phase out, changing that one word to secure a final agreement. cnn s phil black joins me now