California Gov. Jerry Brown issued a less-than-enthusiastic endorsement of Hillary Clinton on Tuesday, calling her the best chance to defeat what he said would be a disastrous victory by Donald Trump.

Brown waited until a week before his state’s June 7 Democratic primary, a vote that could embarrass Clinton on the day she is widely expected to clinch the presidential nomination.

“I have decided to cast my vote for Hillary Clinton because I believe this is the only path forward to win the presidency and stop the dangerous candidacy of Donald Trump,” Brown wrote in what he called an open letter to state Democrats. He spelled out his reasons, including Trump’s opposition to global agreements on climate change, but did not urge Democrats to follow his lead.

Clinton has effectively already won, and it is time to focus on defeating Trump, Brown wrote.

“This is no time for Democrats to keep fighting each other. The general election has already begun,” he wrote. “Hillary Clinton, with her long experience, especially as secretary of state, has a firm grasp of the issues and will be prepared to lead our country on Day One.”

Clinton's campaign emailed a copy of the letter to reporters without comment Tuesday.

Brown praised Clinton rival Bernie Sanders on his way to calling Clinton qualified and capable. Sanders is riding a late surge of support in the nation’s most diverse state and hopes a victory in California would  strengthen his argument that he is the better and more deserving candidate.

Despite winning more pledged delegates overall and never trailing Sanders throughout the long primary fight, Clinton has failed to excite many of her party’s most liberal voters, and suffers a debilitating lack of support from young voters.

Brown’s support follows decades of sometimes acid criticism of both Hillary Clinton and former president Bill Clinton. One of the longest-running feuds in Democratic politics began when Brown ran against Bill Clinton in the Democratic primary in 1992 and won five states.

Brown did something akin to what Sanders is vowing this time. Having lost the nomination to Clinton, Brown pushed to deliver a speech on the floor of the Democratic National Convention. He was denied, but still spoke in support of his own nomination and his campaign themes that included a pledge to battle the "growing concentration of wealth." Sound familiar?

On Tuesday, Brown gave an admiring nod to Sanders’s ability to make that message a central theme in the campaign.

“I have closely watched the primaries and am deeply impressed with how well Bernie Sanders has done. He has driven home the message that the top one percent has unfairly captured way too much of America’s wealth, leaving the majority of people far behind,” he wrote. “In 1992, I attempted a similar campaign.”

He added: “For her part, Hillary Clinton has convincingly made the case that she knows how to get things done and has the tenacity and skill to advance the Democratic agenda. Voters have responded by giving her approximately 3 million more votes – and hundreds more delegates – than Sanders."