Donald Trump's policy position made no call for the mass deportation of millions of undocumented immigrants. (Jabin Botsford/The Washington Post)

This post has been updated.

For more than a year, Donald Trump has stood by his pledge to deport all of the roughly 11 million immigrants believed to be living in the United States illegally. "They have to go," Trump told NBC's "Meet the Press" in August.

Trump took the plan a step further in a November interview with MSNBC's "Morning Joe," when he said he would create a "deportation force," suggesting a policy similar to President Eisenhower's effort that carried undocumented immigrants to the border by the busload in the 1950s.

Throughout the campaign, when reporters asked him whether his proposal was unrealistic or prohibitively expensive or too disruptive to the fabric of American communities, Trump insisted that all undocumented immigrants would be removed if he were elected.

In the past few days, however, the Republican presidential nominee and his associates have suggested Trump might be taking a different approach. On Monday morning, he told "Fox & Friends" that he had been working with the Hispanic community to develop a "fair but firm answer" to the issue of illegal immigration. When asked if Trump would be sticking to his plan for a deportation force, his campaign manager, Kellyanne Conway, told CNN that was "to be determined."

Republican presidential candidate Donald Trump has said over and over he would force undocumented immigrants to leave the country as president. Now a meeting with a Hispanic advisory panel and statements from his surrogates are calling into question whether that's still the plan. (Sarah Parnass/The Washington Post)

Some political commentators have been criticizing Trump for appearing to retreat from the promise. Mass deportation, however, was never part of Donald Trump's official immigration plan. The policy position on immigration that he released last August specifically mentioned deportation only once, in reference to gang members. It also asserted that "all criminal aliens must be returned to their home countries" and called for tripling the number of Immigration and Customs Enforcement officers.

But it made no call for the mass deportation of millions of undocumented immigrants. 

This has become common with Trump. While he often has contradicted himself on policies in speeches and interviews, the official positions detailed on his campaign site have sometimes proved to be better guides to the policies the nominee ultimately endorses.

Trump, who is expected to give a speech on immigration on Thursday, has insisted his latest position is not a flip-flop.

Trump's written immigration plan also called for denying citizenship to the children of undocumented immigrants born in the United States and requiring employers to electronically verify their workers' legal statuses, in addition to his plan to build a wall on the U.S.-Mexican border. But nothing Trump or his advisers have said in the past few days, however, is inconsistent with the proposal the campaign published just over a year ago. It was a detailed document that drew measured praise from the conservative intelligentsia.

Trump has wavered on other parts of his written immigration policy, too. For instance, the document is very critical of the H-1B program, which  provides visas for skilled immigrant workers and is frequently used in the tech industry. It says that Trump, as president, would increase the wages that employers must pay workers with H-1B visas, making it more expensive for U.S. firms to hire foreign labor. The plan also called for firms to hire U.S. workers before immigrants with H-1B visas.

During primary debates, however, Trump said that he thought the program was valuable and an important way for the United States to retain the most talented people from around the world. Later, Trump released a statement contradicting what he had said in the debates and returning to the position the campaign had laid out initially.

"I will end forever the use of the H-1B as a cheap labor program, and institute an absolute requirement to hire American workers for every visa and immigration program," the statement read. "No exceptions."

More from Wonkblog:

The huge immigration problem that Donald Trump's wall won't solve

What's incredible about Republicans' views on immigration is how much they've changed

The biggest ideas underpinning the anti-immigration movement aren't backed up by data