Mitt Romney said Friday he wouldn't rule out supporting the Libertarian White House ticket after pledging to not vote for either the Democratic or Republican presumptive nominees.
"That's something that I'll evaluate over the coming weeks and months," Romney said of voting for Johnson. "I'm not ruling that out."
Romney acknowledged it would be "very hard" to support a candidate that is in favor of liberal social policies such as legalizing recreational marijuana, but said he'd "look carefully" at the Libertarian ticket.
Romney said Johnson's running mate, former Massachusetts Gov. Bill Weld, "is someone who I respect enormously."
Weld was governor a decade before Romney served at the helm in Massachusetts. 
"He was a fine governor, a fine friend, a supporter of mine both in 2008 and 2012," Romney said. "If Bill Weld were at the top of the ticket it would be very easy for me to vote for Bill Weld for president."
"Both of them have enormous drawbacks, I'm not going to choose which one is worse," Romney said.
He reiterated in the interview that he won't personally seek an independent White House campaign and also doesn't think launching a third-party bid generally is possible at such a late point.