One of Hillary Clinton's most prominently speculated-about VP picks slammed George Zimmerman's gun auction

Labor Secretary Tom Perez, a prominent surrogate for Hillary Clinton, said Thursday he's not surprised that George Zimmerman has a controversial way of attempting to raise money to defeat the former secretary of state.

On Wednesday evening, Zimmerman posted an auction notice on gunbroker.com for the handgun that he used to shoot unarmed black teenager Trayvon Martin during a struggle in 2012. In a description of the gun, Zimmerman said he'd dedicate some of the proceeds to stopping Clinton's "anti-firearm rhetoric."

Perez, who has been prominently speculated about as a potential Clinton running mate, responded during a conference call Thursday.

He told Business Insider he was not surprised that Zimmerman would oppose Clinton's gun-safety proposals, which Perez took as an implicit endorsement of presumptive Republican nominee Donald Trump.

"It wouldn't surprise me if George Zimmerman wanted to be on Donald Trump's side, because they share the same values," Perez said.

From his perch as the Department of Justice's assistant attorney general for civil rights, Perez launched an investigation into whether Martin's death was a "hate crime." Perez left to became the secretary of labor before the investigation concluded, but the department did not end up filing charges.

Repeatedly labeling Trump a "trainwreck" during Thursday's press call, Perez emphasized the gulf between Clinton and Trump on numerous issues, including gun safety.

"Hillary Clinton has been standing up for common-sense gun-safety laws for some time, and she's going to continue to do that. Because that's one of the defining issues of this election. It's yet another issue where the two of them are in such a different place," Perez said.

Perez has been floated as a potential vice-presidential pick for Clinton largely due to his strong relationships with many progressive communities. During Thursday's press call, however, the secretary again brushed off speculation about his vice-presidential ambitions.

"I have had no conversations about that, and I am glad about that, because I continue to do my day job, and in my spare time, I'm helping Sec. Clinton get elected," Perez said.