Early this week American President Donald Trump praised his Secretary of State Rex Tillerson's former company ExxonMobil on Twitter and the White House website when Tillerson likely continued to hold stock in the company.

On Monday 6 March Trump congratulated the oil giant in a tweet for a "job-creating investment program" the company is planning that will pour $20bn (£16bn) into the US Gulf Coast region by building new liquefied natural gas, oil refining, and chemical-manufacturing projects there. The investment started in 2013 and will run to 2022.

"This is exactly the kind of investment, economic development and job creation that will help put Americans back to work," President Trump said in a White House press release.

Before Tillerson started through the process of Senate hearings – so that he could be confirmed as Secretary of State – he signed an ethics agreement, and acknowledged that he owned 600,000 shares of Exxon stock and 2 million other shares that would normally have been paid out over a decade during his retirement.

The value of his ExxonMobile stock holdings was more than $50m and deferred payouts between $1m and $5m. He also promised to divest himself of investments in 156 other companies, including Apple, Airbus Group, AT&T, Caterpillar, GE, and GM.

"I will divest my stock in ExxonMobil within 90 days of my confirmation," Tillerson said in his agreement, indicating that he would avoid taking any decisions as Secretary of State during that time that would have "a direct and predictable effect on the financial interests of ExxonMobil."

He was also willing to waive other benefits too, including ExxonMobile's retiree medical benefits, the use of a product discount credit card, and other perks. All told, he would be forgoing about $7m in compensation owed to by the company.

Tillerson was confirmed on 1 February, meaning the 90-day period ends in early May. He said immediately after his confirmation that he would make a "clear, clean break" from the company.

But what is not certain is how much ExxonMobile stock Tillerson retains at this moment, and whether it could be impacted by President Trump's statements.

Trump's recognition of ExxonMobile coincided with a slight bump in the stock. But any remaining shares held by Tillerson could feel the impact of decisions made by the president as they are being divested.

When asked on on Tuesday 7 March if Tillerson was behind Trump's tweets, State Department deputy spokesman Mark Toner said he wasn't and added that the Secretary is "committed to federal ethics rules" and that "he's continuing to carry out and meet the terms of this agreement."

IBTimes UK requested clarification from the State Department of how much ExxonMobile stock Tillerson continues to hold. "The Secretary promised to divest by a certain date and that is what he is going to do," a State Department spokesperson responded.

US Secretary of State Rex Tillerson takes his seat for a meeting with his Japanese and South Korean counterparts at the World Conference Center 16 February in Bonn, Germany Reuters/Brendan Smialowski