U.S. President Donald Trump looked set on Wednesday to authorize steep tariffs on imported steel and aluminum this week as he stepped up pressure against China to develop a plan to reduce its trade imbalance with the United States by $1 billion.

A day after the resignation of his economic adviser, Gary Cohn, and despite strong pushback from Republican lawmakers, the White House said Trump was ready to move forward with his tariffs plan by the end of the week.

Some reports suggested he could sign the presidential proclamation as soon as Thursday.