The United Nations has extended a contract with Russia's Tyumenaviatrans airline to provide transport support for a peacekeeping mission in Sierra Leone, an airline official told RIA Novosti on Monday. The official said that in keeping with the 4.1-million-dollar contract, extended until December 26, 2002, the airline will provide aircraft for the U.N. mission. The airline's specialists will operate two Russian-built Mi-8MTV helicopters, which have already served the U.N. mission in the African state since December 2000. At present, four Mi-8MTV, two Mi-8T and two Mi-26T helicopters, belonging to Tyumenaviatrans, are used in Sierra Leone. According to the airline official, the U.N. has extended the contract with Tyumenaviatrans for the fourth time. In addition, the airline has won seven tenders this year to provide transport support for U.N. peacekeeping missions in Sierra Leone, Western Sahara, Eritrea and East Timor. In all, 19 helicopters of Tyumenaviatrans are now used abroad, including three Mi-26s, 11 Mi-8MTVs, and five Mi-8Ts.