Counselor to the President John Podesta will take on a senior role in Hillary Clinton's as yet undeclared Presidential campaign when he departs the White House next month, according to a published report.

The Wall Street Journal, citing three people with the matter, reported that Podesta has sat in on informal meetings of Clinton aides that have have discussed a potential presidential campaign in 2016. The former Secretary of State and Senator from New York has not yet formally announced her candidacy. However, the Journal reports that Podesta's planned move is seen as the clearest sign yet that she will run.

It remains unclear what role Podesta would play in a presumptive Clinton campaign, the Journal reported that he would likely become campaign chairman.

Podesta served as White House chief of staff for the final 27 months of former President Bill Clinton's second term in office. He became Counselor to President Barack Obama at the beginning of 2014, and has played a key role in advising the president on energy policy.

Podesta initially told Reuters last week that he would depart the White House "in early February," a few weeks after Obama delivers the State of the Union address Jan. 20. When discussing a possible role in a Clinton campaign, he said, "If she decides to run, I told her I'd do anything I can to help her."

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