Scott Walker
Wisconsin Gov. Scott Walker is set to announce his endorsement Tuesday morning. In this photo, Walker speaks at the American Action Forum in Washington, D.C., Jan. 30, 2015. Getty Images/Win McNamee

Wisconsin Gov. Scott Walker will endorse one of the Republican presidential candidates Tuesday during a Milwaukee radio show appearance. The announcement will come just a week before the Wisconsin primary.

Walker had earlier signaled that he may choose either Texas Sen. Ted Cruz or Ohio Gov. John Kasich. Donald Trump late Monday expressed his confidence that Walker will not endorse him.

Last week, during an interview Walker made it clear that he would back Cruz as Kasich “cannot” win the nomination. He added that he would time his endorsement for “maximum impact,” the Wall Street Journal reported.

Walker also said last week that “Ted Cruz is the only one who's got a chance other than Donald Trump to win the nomination, statistically.”

According to the Journal, Walker is not expected to campaign with Cruz during his two campaign stops scheduled Tuesday in the Milwaukee suburbs. Walker is scheduled to be at events Tuesday in Plymouth, Green Bay and Rothschild.

The 48-year-old entered the 2016 Presidential race as an early front-runner but exited the race well before voters in the early primary states went to the polls.