Wall St poised for weak open as rate worries keep Treasury yields elevated

WALL Street's main indexes were on track for a lower open on Tuesday as investors continued to grapple with the prospects of a prolonged restrictive monetary policy by the Federal Reserve and its subsequent impact on the economy.

Adding to investor anxiety was the likelihood of a partial shutdown of the U.S. government by Sunday, which, according to ratings agency Moody's, is likely to be a "credit negative".