By William L. Watts
LONDON (MarketWatch) -- The three-month U.S. dollar London interbank offered rate, or Libor, was fixed at 0.5363% Tuesday, up from 0.5097% on Monday. The rate is the highest since early July of last year and has been on the rise since the spring on growing worries over sovereign debt problems in the euro zone. The spread between Libor and overnight index swaps have also widened, a move that's viewed as a sign of banks growing more reluctant to lend to each other.
