As soon as President-elect Donald Trump made official his nomination of Exxon Mobil CEO Ken Tillerson to be secretary of state, U.S. senators of both parties began to voice strongly worded concerns about the nominee's ties to Russian strongman Vladimir Putin.

But Tillerson, 64, will face his most spirited opposition from a decidedly left-of-center group funded in large part by George Soros, the Hungarian-born billionaire known as "the paymaster" of leftist organizations.

Global Witness, which styles itself as an environmental watchdog group, charged Monday that under Tillerson's watch, Exxon Mobil has been a part of "misleading the public about what it knew of the threat from climate change, for which it's now under investigation by the New York Attorney General."

Because of Tillerson's leadership of a corporation accused of holding back information on climate change, Corinna Gilfillan, head of Global Witness's U.S. office, told reporters that "he shouldn't become our top diplomat or global representative on climate change."

An even more serious charge thrown at the secretary of state-designate by Global Witness is that their investigations have shown "how ExxonMobil or its corporate predecessor Mobil have engaged in questionable transactions with governments of oil-rich countries, including Nigeria, Kazakhstan, Equatorial Guinea, and Angola."

Such deals, according to Global Witness's Gilfillan, "have contributed to entrenching poverty, fueling instability and violating human rights in some of the world's most volatile regions."

This charge may be on shallow ground, according to a leading Africa expert who spoke to Newsmax.

"Is Exxon Mobil's record in developing oil economies worse than Royal Dutch Shell's or ENI's or BPs?" asked Patrick Smith, editor of the much-read and influential Africa Confidential, "Probably not — they have more financial power and more weight to throw around.

But, Smith quickly added, "When a government says no, they back down. Let me give you the example of Exxon Mobil's efforts to buy their way into Ghana. The then government in Accra held firm after much lobbying and pressure . . . then Exxon Mobil backed down.

"So the horrors of oil production in Africa are very much a joint venture between bad governments and big oil . . . There are no innocent parties except those who stay out."

Of Global Witness, Smith concluded that "it's funded largely by George Soros, draws credible research but also has to burnish their campaigning credentials to get heard above the mêlée."