Senate Majority Leader Harry M. Reid (D-Nev.) speaks to reporters last week on Capitol Hill. (Susan Walsh/AP)

President Obama could use his executive authority to change the nation's immigration policy "as soon as this week," according to Senate Majority Leader Harry M. Reid (D-Nev.).

"I think it should be done now," Reid added in an interview with Univision.

The Senate leader provided a spirited defense of Obama's stated plans to take action in the interview by detailing the legal justification and reminding viewers that previous presidents have used executive authority to change immigration laws.

"Why would this be such an issue with the Republicans? They're looking for an excuse. An excuse not to help people who so deserve it. This has been going on for a long, long time. We've adjusted stuff in the past; we should do it now," he said.

Reid's comments to the nation's dominant Spanish-language television network and its popular national newscasts were designed to signal to Hispanic viewers — the voting bloc most concerned about immigration -- that Democrats continue to support Obama’s plans. At one point, Reid made clear that Democrats “have his back.”

Congressional Republicans have warned Obama that he risks upending any opportunity for cooperation on legislation in the final two years of his presidency if he takes action on immigration. Reid said in the interview that he hopes the president's decision doesn't jeopardize opportunities for congressional productivity.

"Immigration shouldn’t prevent Senator [Minority Leader Mitch] McConnell and I from working together," he said. "It’s so clear. It’s been going on since Dwight Eisenhower. Why would this cause any problem between McConnell and Reid? I don’t — I’ve said many times in the last week or so, the election's over, we should move on and get something done for the American people."

Reid also openly doubted whether a bipartisan bill authorizing construction of the Keystone XL pipeline will earn the 60 votes needed Tuesday night. He said he doesn't support the bill and that Obama should veto the legislation: "Of course he should."