Yoon’s veto of a probe with an independent panel came after the prime minister described the opposition-backed bill as politicised and potentially in breach of the constitution.

“The pain from the disaster cannot be used as a tool to justify political strife and a possibility of unconstitutionality,” Prime Minister Han Duck-soo told a cabinet meeting, denying an earlier investigation by police and prosecutors was flawed.

The move to block the bill has been criticised by relatives of the victims and opposition party officials who have long argued the government’s handling of the disaster had been inadequate.

Park Young-soo, a mother who lost her son in the crowd crush, accused the government of being “petty” by blocking the enquiry and offering financial compensation instead.

“That’s not what we have been fighting for more than a year for,” Park told Reuters.