https://www.reuters.com/article/us-el-salvador-bitcoin-imf/imf-sees-legal-economic-issues-with-el-salvadors-bitcoin-move-idUSKCN2DM1TP >NEW YORK/LONDON (Reuters) -The International Monetary Fund said on Thursday it has economic and legal concerns regarding the move by El Salvador to make bitcoin a parallel legal tender, further clouding the outlook for an IMF-backed program and widening spreads on the country's bonds.