The battle between ride-sharing apps Uber and Lyft has been brutal and very public, with claims that Uber was having its employees call and cancel Lyft rides to tie up the drivers and a leaked plan that laid out how Uber was sending ambassadors to poach Lyft drivers.

Apparently, however, Uber CEO Travis Kalanick took it even further than that.

In a recent Vanity Fair profile, Kalanick admitted that he went to potential investors to thwart Lyft's fundraising efforts. 

"We knew that Lyft was going to raise a ton of money," Kalanick told Swisher. "And we are going [to their investors], 'Just so you know, we're going to be fund-raising after this, so before you decide whether you want to invest in them, just make sure you know that we are going to be fundraising immediately after.'"

This shouldn't come as much of a surprise considering the questionable business tactics Uber has reportedly taken on recently. But the comment reveals another layer of how far Kalanick is willing to go to succeed and sideline its rivals.

Kalanick admits that he can sometimes take things too far.

"Look, I'm a passionate entrepreneur," he told Swisher. "I'm like fire and brimstone sometimes. And so there are times when I'll go--I'll get too into the weeds and too into the debate, because I'm so passionate about it."

But others don't view this approach so positively. Take this venture capitalist's description of Kalanick: "It's douche as a tactic, not a strategy."