What does "go back on" mean?

To be treacherous or faithless to; to betray.

What is a synonym for "go back on"?

Common synonyms include: abandon, back, back down, back out, be unfaithful, beg off.

verb

verb ·Rare ·Advanced level

Verb

1
To be treacherous or faithless to; to betray.
"to go back on friends"
2
fail to fulfill a promise or obligation wordnet
3
To fail to keep; to renege on.
"to go back on one's promises"
4
Used other than figuratively or idiomatically: see go, back, go back, on.
"He went back on the same path."

"BBC News On Sunday Iranian President Mahmoud Ahmadinejad said his country would not go back on its nuclear programme."