NEW YORK (Reuters) - Standard & Poor's on Wednesday cut Greece's sovereign credit rating further into junk territory, lowering it to CC from CCC, saying the European Union's proposed debt restructuring puts the country into a "selective default."

Euro zone leaders agreed on a second, 109 billion euro ($158 billion) package for debt-stricken Greece last Thursday.

The outlook on the debt is negative, S&P said in a statement.

(Reporting by Daniel Bases and Caryn Trokie, Editing by Chizu Nomiyama)