Less than a week before President Donald Trump signed an executive order rolling back major elements of the Obama administration’s climate change policies, one of the largest gas and oil companies in America advised the White House to remain a participant in the Paris climate agreement.

In a letter sent March 22 to the White House, Exxon Mobil urged the Trump administration not to pull out of the Paris Agreement, calling the landmark deal reached in 2015 an “effective framework for addressing the risks of climate change” and the “first major international accord” to reduce greenhouse gas emissions.

In response to news of the letter, Sen. Bernie Sanders (I-Vt.) tweeted Wednesday that it was “pathetic that the largest oil company in the world” has to tell the president about climate change.

It is pathetic that the largest oil company in the world understands more about climate change than the president of the United States. https://t.co/5EPP05KNUE — Bernie Sanders (@SenSanders) March 29, 2017

Exxon Mobil’s letter was sent in response to a White House request for the company’s position on the Paris climate agreement, said Alan Jeffers, a company spokesman who shared the letter with The Huffington Post.

In it, Exxon Mobil’s manager of environmental policy and planning, Peter Trelenberg, said that the U.S. is “well positioned to compete within the framework of the Paris Agreement.” Trelenberg argued that the agreement would also expand the country’s use of natural gas, which he says is the “cleanest-burning and least carbon-intensive fossil fuel.”

The letter also argued that the challenge to combat climate change could lead to technological advances and the U.S. should keep policies in place that would support those advances.

The Exxon Mobil official added: “It is prudent that the United States remain a party to the Paris Agreement to ensure a level playing field, so that global energy markets remain as free and competitive as possible.”

A White House official told reporters that the administration has not yet decided whether the U.S. government will withdraw from the climate deal, according to CNN.

And while Tuesday’s “Energy Independence Executive Order,” which Trump has called an “energy revolution,” did not directly address the Paris accord, it could prevent the U.S. from meeting the commitments it made under the agreement.

Exxon Mobil is currently under investigation for allegedly lying to the public about its climate change research. Rex Tillerson, the energy giant’s former CEO and now the secretary of state, has previously suggested that the U.S. stay committed to the Paris Agreement.

Exxon Mobil refused to comment on the executive order and how it would affect U.S. commitments to the climate accord.