renege on

renege on (something)

To withdraw from or fail to do or carry out something, such as a given commitment, promise, plan, or situation. People are beginning to worry that the president is going to renege on his campaign promises. The merger was all set to move forward, but the other company reneged on the agreement at the last possible moment.
See also: on, renege
Farlex Dictionary of Idioms.

renege on something

to go back on one's promise or commitment. I am mad at you because you reneged on your promise! I did not renege on what I promised.
See also: on, renege
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

renege on

v.
To fail to carry out some promise or commitment; go back on a promise or commitment: If I had known that you would renege on your contract, I never would have hired you.
See also: on, renege
The American Heritage® Dictionary of Phrasal Verbs.
See also:
  • be (batting) on a losing wicket
  • stop at
  • stop at (something)
  • fall flat
  • take a gamble
  • talk (oneself) out of (something)
  • rats deserting a sinking ship
  • fail at life
  • take a chance on
  • take a chance on (someone or something)