Story highlights Bernie Sanders warned Hillary Clinton against picking a moderate Democrat as vice president

Sanders wouldn't comment on running with Clinton, saying he's still trying to win the nomination

Washington (CNN) Bernie Sanders is warning Hillary Clinton against picking a moderate Democrat as her running mate.

But he's staying away from criticizing his rival over her private email use during her tenure as secretary of state, continuing to downplay an issue that Republicans have used heavily against Clinton.

Still locked in a heated primary battle against Clinton, Sanders said Sunday on NBC's "Meet the Press" that she should find a vice-presidential pick who doesn't have a cozy relationship with corporations.

"I would hope, if I am not the nominee, that the vice-presidential candidate will not be from Wall Street, will be somebody who has a history of standing up and fighting for working families, taking on the drug companies whose greed is doing so much harm, taking on Wall Street, taking on corporate America, and fighting for a government that works for all of us, not just the 1%," Sanders said.

The Vermont senator's vice-presidential prerequisites look like a list of his campaign's top talking points. But his comments also served to lay out terms for Sanders embracing Clinton if she secures the Democratic nomination at the party's convention in Philadelphia in July.

Read More