climb down

(idiomatic, sometimes hyphenated) An abandonment, withdrawal from, or softening of a previously expressed opinion, policy, argument, etc.

Example: 2003 Aug. 7, "Hope for Korea," Pittsburgh Post-Gazette, p. A20 (retrieved 30 June 2011):
  It is interesting to speculate on what combination of factors acted within the Bush administration to bring about the climb-down from its previous position.
2003 Sep. 27, "Mulyam shows his ‘secular’ face again, hits out at BJP," India Times (retrieved 30 June 2011):
  His climb-down from the "hard, secular" image was mainly to widen his support base.
2010 April 24, "Editorial: Dalton McGuinty schooled on sex ed," Toronto Sun (Canada) (retrieved 30 June 2011):
  Hours before his climb down, the premier's own cabinet ministers had vigorously defended the curriculum.