ZAGREB, Jan 26 (Hina) - Croatia forwarded a letter to the United Nations Security Council's (UNSC) President, expressing regret at Serbian President Boris Tadic having used a discussion on the UN mission in Kosovo before the Council to level groundless accusations at President Stjepan Mesic over his warnings about possible consequences of disintegration of Bosnia-Herzegovina. Mesic warned about the policy pursued by the Bosnian Serb leader Dodik.