UPDATE 1-Brazil's Usiminas seeks $1 bln loan refinancing, sources say

SAO PAULO, Feb 12 (Reuters) - Usinas Siderúrgicas de Minas Gerais SA is negotiating with banks refinancing about 4 billion reais ($1 billion) in loans maturing in the next two years as Brazil's largest listed flat steel producer faces cash pressures to repay debt, four sources with direct knowledge of the matter said on Friday.