Gary Cohn, who resigned on Tuesday as the director of President Donald Trump's National Economic Council, apparently wasn't in a position to give his all at the White House.

The news website Axios reported that Cohn spent his time reviewing the basics of economics at the White House and told the president in February that he was working at just 20% of his capacity.

Gary Cohn, who resigned on Tuesday as the director of the National Economic Council and President Donald Trump's top economic adviser, apparently wasn't in a position to give his all at the White House.

Citing West Wing sources, the news website Axios reported that in February, after Trump gave a well-received State of the Union address and another big speech at the World Economic Forum in Switzerland, Cohn told the president, "I'm working at like 20% of my capacity."

Cohn, a former Goldman Sachs executive, spent much of his time working for Trump explaining conventional economic wisdom and broadly accepted concepts, Axios said. Recently, he pressed Trump not to go ahead with imposing tariffs on imports of steel and aluminum — a battle Cohn appears to have lost.

Though Cohn was part of the successful push for the new GOP tax law, he later made few appearances pushing for infrastructure spending.

"Cohn said that if Trump could put him in a role where he would use 80% or 90% of his brain capacity, he'd stay," Axios reported.

"It has been an honor to serve my country and enact pro-growth economic policies to benefit the American people, in particular the passage of historic tax reform," Cohn said in a statement announcing his departure. "I am grateful to the President for giving me this opportunity and wish him and the Administration great success in the future."