Sen. Rand Paul, R-Ky., said that if Vice President Mike Pence were still a congressman he would oppose President Trump’s national emergency declaration.

But Pence disagreed.

That's what three people familiar with their exchange told the New York Times after a lunch Pence had with Republican senators.

In the meeting, the sources say that Paul pointed to former President Barack Obama's executive order to protect immigrants who were brought to the U.S. illegally as children, known as Deferred Action for Childhood Arrivals program as a comparison.

But Pence said that Trump's declaration of a national emergency is vastly different from Obama's use of executive power, and while he opposed Obama’s effort to protect illegal immigrants, he does not oppose Trump’s to secure the southern border.

[Opinion: Why is Obama allowed ‘executive discretion’ on immigration, but Trump isn't?]

A Paul spokesman confirmed that the Kentucky senator raised concerns over the emergency declaration, but did not make the comparison to DACA.

Trump declared a national emergency earlier this month, claiming there is a humanitarian crisis at the U.S.-Mexico border with illegal immigrants bringing drugs and crime, including human trafficking, into the country.

The president declared an emergency in order to obtain the money deemed necessary to build a border wall. Trump had threatened to do so during the partial government shutdown in an effort to break the stalemate over funding with congressional Democrats, but the $5.7 billion he wanted was not included in the final federal government funding bill.