repudiate
verb [ T ]
uk/rɪˈpjuːdieɪt/ us LAW
to decide that an agreement is no longer effective and that you will not do what it says you must do:
repudiate a contract/agreement Failure to deliver on time will entitle the buyer to repudiate the contract.
FINANCE
to decide that you will not pay back money that you owe:
The Soviet Union repudiated its debt after the 1917 Revolution.
repudiation
noun [ C or U ]
Where the buyer accepts the seller's breach as a repudiation of the contract, the buyer will be entitled to damages.