Cooper Allen, and Katie Smith

USA TODAY

Hillary Clinton has turned down Fox News' invitation to take part in another Democratic primary debate with Sen. Bernie Sanders, her campaign said Monday.

"As we have said previously, we plan to compete hard in the remaining primary states, particularly California, while turning our attention to the threat a Donald Trump presidency poses," said Jennifer Palmieri, the Clinton campaign's communications director, in a statement.

Sanders recently accepted an invitation to take part in the debate, which was to be held in California ahead of its June 7 primary.

“I am disappointed but not surprised by Secretary Clinton’s unwillingness to debate before the largest and most important primary in the presidential nominating process," Sanders said in a statement in which he added a few digs at Clinton.

Given the troubles facing California, Sanders said they should have a debate out of "respect for the voters" of the state.

“I also would suggest that Secretary Clinton may want to be not quite so presumptuous about thinking that she is a certain winner," he added. "In the last several weeks, the people of Indiana, West Virginia and Oregon have suggested otherwise.”

Bill Sammon, Washington managing editor for Fox News, said the network was "disappointed" that Clinton declined the debate, "especially given that the race is still contested and she had previously agreed to a final debate before the California primary.”

Clinton holds a significant lead over Sanders in the delegate race and is within 100 of the 2,383 needed to clinch the party's nomination, according to the Associated Press, when superdelegates — party leaders and elected officials free to support any candidate — are factored in. California has 475 pledged delegates at stake in its primary.

Clinton and Sanders last debated on April 14 in Brooklyn, which, unless something changes, appears to have been their final face-off of the 2016 campaign.