Cooper Allen

USA TODAY

Donald Trump says his "major" address on immigration will come Wednesday in Arizona, a speech that has been discussed, and delayed, for days amid signs the GOP presidential nominee is shifting his position on his signature issue.

Trump had already scheduled an event in Arizona — despite the fact that his Arizona campaign director had said it was canceled Friday — and made clear on Twitter Sunday night what the focus of his remarks would be.

"I will be making a major speech on ILLEGAL IMMIGRATION on Wednesday in the GREAT State of Arizona," Trump wrote, adding that he expected "big crowds."

Trump's speech will be closely watched in light of his recent rhetoric on an issue that helped propel him to the Republican presidential nomination.

In interviews last week, he said he was open to a "softening" of his policy when it came to undocumented immigrants already in the country

Has Trump actually changed his stance on immigration? It's not clear

During an appearance Saturday in Iowa, he focused on the need to fashion an immigration policy geared to "prevent crimes." Trump has previously vowed to deport all of the nation's approximately 11 million undocumented immigrants.

In Iowa, Trump vows to remove 'thugs and drug cartels' on Day 1

Some of Trump's most prominent backers have said the GOP presidential nominee's position remains consistent.

"Nothing has changed about Donald Trump's position on dealing with illegal immigration," Indiana Gov. Mike Pence, Trump's running mate, said on CNN Sunday, adding that the real estate mogul's previous proposal for a deportation force "was a mechanism, not a policy."