Please I need a detail response to the below;

The President of the United States is concerned about the declining number of American companies engaged in the manufacture of computer chips. In order to reinvigorate U.S. computer chip manufacturers, the President has proposed that the United States unilaterally impose an absolute ban upon the importation of computer chips from Japan for an indefinite period of time to be determined in his complete discretion. The President has asked you whether his proposal is legal pursuant to the GATT. What is your response? Please explain the basis for your conclusions.