US STOCKS-Wall St set to open lower as Greek talks falter
* Greece talks suffer setback after IMF quits
* May Producer Price index up 0.5 pct vs est 0.4 pct
* Twitter rises after CEO quits
* Futures down: Dow 60 pts, S&P 7.5 pts, Nasdaq 23 pts (Adds details, comment, updates prices)
By Tanya Agrawal
June 12 (Reuters) - Wall Street was set to open lower as optimism regarding a resolution of the Greek debt crisis faded with the International Monetary Fund pulling out of bailout talks.
Greece said it would not cross its "red lines" as it looked to intensify political negotiations for an agreement, saying IMF's move was designed to put pressure on Athens.
Investors are also edgy ahead of the U.S. Federal Reserve's Open Market Committee meeting next week, which may provide clues regarding the timing of an interest rate hike.
"Investors don't want to make any big moves ahead of the meeting and Greece certainly continues to be a big factor," said Adam Sarhan, chief executive of Sarhan Capital in New York. Continuación...