The head of the MTA says he's confident the three new stations of the Second Avenue Subway will open by the end of next year despite warnings the agency may miss the target date.

As NY1 first reported last week, an independent engineering consultant warned the MTA that work on the tracks and entrances has fallen behind at the new 72nd Street station.

The consultant also pointed out that work crews still don't have a permanent power source at the 86th Street station.

"The governor has been very clear that the December 31, 2016 is the date that we're meeting," said MTA Chairman Thomas Pendergast. "So we're doing everything to make sure that that's the case. And right now we're confident.

"But there's risks with anything that we do. But we're confident we're going to meet that December 31, 2016 date for the phase one of Second Avenue."

The $4.5 billion first phase includes the extension of the Q train with stations at 72nd, 86th and 96th Streets.