Sarah Sanders rages at Joe Biden ahead of Iowa speech: He 'allowed Russia to interfere with our election'
Sarah Sanders speaks to reporters outside the White House (Mark Knoller/Twitter)

White House Press Secretary Sarah Sanders said on Tuesday that former Vice President Joe Biden "allowed Russia to interfere with our election."

During a gaggle outside the White House, Sanders spoke to reporters about the news that Biden is expected to call President Donald Trump an "existential threat" later on Tuesday.

"I'm sure Biden has a lot of questions he needs to answer himself," Sanders reportedly said.

The press secretary also accused Biden of being "part of the administration that allowed Russia to interfere in our election... they allowed China to continue to grow."

Read some of the reports from Sanders' gaggle below.