The veto means that the governor will have to reopen negotiations with the Legislature to win approval for his plan to close a nearly $10 billion gap. The plan relies on extending some taxes that are set to expire this year, and for it to pass, Mr. Brown needs the support of two Republicans in each legislative chamber. Those votes have been elusive.
Many lawmakers said they had expected the governor to continue to negotiate with Republicans, but few expected the veto. It was the first budget veto since at least the 1920s.