'go back on a promise' is correct and usable in written English.
You can use it when you want to express someone has broken an agreement or does not follow through with what was previously promised. Example: My boss went back on his promise to give me a raise after I worked hard for the company.
Last winter, a wave of popular acclaim, carefully staged by the governing General People's Congress GPCC), "forced" the president to go back on a promise not to run in the elections set for September 20th.
Mr Clegg had to go back on a promise not to raise tuition fees, for instance, presenting a challenge for a party largely comprised of moderate voters on the left and the right.
Even though I might find it easy to go back on a promise I made in order to meet a personal objective, she believes (as I do to this day) that my word (and others' ability to trust what I say) is more important than achieving any potentially short-sighted goal.
Don't go back on a promise.
His counterpart, Adam Stoll, then accused Mr. McCall of going back on a promise not to engage in negative campaigning.
Justin King, the chief executive of Sainsbury's, has been accused of going back on a promise he made to local campaigners at a meeting in August last year.
"Launching his campaign by going back on a promise to voters would be dishonest, and exposes his politics of hope as empty rhetoric out of a typical politician".
The decision to block the site has also sparked condemnation from Malaysians, who said the government has gone back on a promise not to censor the internet.
Oupa Lebogo, general secretary of the Creative Workers Unionn of South Africa, said the World Cup organising committee went back on a promise to consult it about the concert.
As my colleagues Neil MacFarquhar and Alan Cowell report, the Syrian authorities on Friday went back on a promise to allow a Red Cross convoy with food and medical supplies into Baba Amr, a rebellious neighborhood in the city of Homs where thousands of residents have endured weeks of heavy bombardment.
Most of the footage used to construct the fictional report was recorded during the second trial of Mr. Khodorkovsky, who was arrested on charges of fraud in 2003, after he appeared to challenge Mr. Putin by raising the issue of rampant corruption during a live television broadcast and going back on a promise to stay out of politics.
