 Kosovo's independence was gradually recognized by the United States and numerous European Union countries, leading to strain in their relations with Serbia.Prime Minister Vojislav Koštunica of the Democratic Party of Serbia (DSS) offered in late February to the Democratic Party (Serbia) (DS), which holds governmental majority, a restructuring of the governmental contract including an annex according to which Serbia can continue European exclusively with Kosovo as its integral part.The controversy was further heated up when Olli Rehn, the European Commissioner for enlargement of the European Union, offered to continue negotiations with Serbia.