Exxon Mobil and FTC reach agreement to close $60 billion Pioneer deal.

• An agreement was reached between regulators and Exxon that prevents Scott Sheffield, the former CEO of Pioneer, from joining the Exxon board.
• In October, Exxon announced a $59.5 billion all-stock deal for Pioneer.
• Exxon stated that the acquisition would significantly increase its production in the Permian Basin.

The Federal Trade Commission has approved 's $60 billion acquisition of after reaching an agreement with the energy giant, a source familiar with the matter told CNBC.

The FTC has agreed not to block the deal between Exxon and Pioneer, as long as Scott Sheffield is prohibited from joining the Exxon board, according to a source.

According to the source, the reason for the push to remove Sheffield was because of his past talks with OPEC.

Bloomberg News first reported the agreement, but neither Exxon nor the FTC have commented on it.

In October, Exxon announced an all-stock deal for Pioneer worth $59.5 billion, stating that the acquisition would significantly increase its production in the Permian Basin.

Exxon chairman and CEO Darren Woods stated in a press release that Pioneer is a clear leader in the Permian with a unique asset base and people with deep industry knowledge. The combined capabilities of our two companies will provide long-term value creation well in excess of what either company is capable of doing on a standalone basis.

Shares of Exxon and Pioneer were both little changed in extended trading Wednesday.

— CNBC's Pippa Stevens and Mary Catherine Wellons contributed reporting.