Hillary Clinton has yet to announce whether she will run for president in 2016, but preparations for a campaign launch appear to be underway. The former secretary of state can already count on top White House adviser John Podesta to join a presidential bid, the Wall Street Journal first reported Tuesday.

Podesta, who has recently appeared at informal meetings of Clinton aides, is leaving the White House in February to join Clinton’s inner circle as a senior adviser, the Journal reported, citing three people familiar with the matter.

Podesta founded Washington-based think tank Center for American Progress in 2003. He is  the outgoing Counselor to President Barack Obama and has been a leading force behind the administration’s energy and climate policies. The 65-year-old Chicago native negotiated an agreement with Chinese President Xi Jinping to jointly reduce greenhouse-gas emissions, according to the White House.

A White House official confirmed with the Journal that Podesta does indeed plan to leave the administration in February, but would not comment on his prospective plans. Podesta would likely be Clinton’s campaign chairman if she decided to run, the Journal reported, citing people familiar with the discussions.

In an interview that aired in mid-November on PBS’s Charlie Rose, Podesta reportedly said, “If she runs, as I hope she will, I will do whatever she asks me to do, but right now she has not made a decision to run.”

Podesta has deep ties with the Clintons. He served as chief of staff in Bill Clinton’s second term and has maintained a top role in the family’s charitable foundation. The former president praised Podesta when he joined the Obama administration in 2013. “He’s very straight forward. He doesn’t play games with people. You always know where he stands,” Bill Clinton reportedly told the Journal.