Brazil rate future yields up, currency flat after S&P downgrade

SAO PAULO, Jan 12 (Reuters) - Yields on Brazilian interest rate futures inched up on Friday after ratings agency S&P lowered the country's sovereign credit rating to BB-, citing a greater risk of policy uncertainty amid this year's general election.

The Brazilian currency weakened slightly at open before turning flat in early trade. (Reporting by Ana Mano; Editing by Alison Williams)