Speaking during a 60 Minutes interview to be aired on Sunday, President-elect Donald Trump praised his election opponent, Hillary Clinton, calling her “very strong and very smart.”

Appearing with the incoming First Lady Melania Trump and four of his children, Trump recalled the call Mrs. Clinton made to the GOP nominee the night of the election, after her defeat had become clear.

"Hillary called, and it was a lovely call,” Trump told Lesley Stahl. “And it was a tough call for her, I can imagine. Tougher for her than it would have been for me - and for me it would have been very, very difficult. She couldn't have been nicer. She just said 'Congratulations, Donald. Well done.' And I said 'I want to thank you very much. You were great competitor. She's very strong and very smart."

The 45th President also spoke with former President Bill Clinton over the phone, with the latter calling Trump’s campaign “amazing”.

Bill Clinton "called last night. He couldn't have been more gracious. He said it was an amazing run, one of the most amazing he'd every seen. He was really nice.”

“He's a very talented guy - both of them, I mean, this is a very talented family."

Trump also broached the subject of healthcare reform, touching upon his campaign promise to repeal and replace the Affordable Care Act – popularly known as “Obamacare”.

In response to a question by Stahl, Trump said he would try to retain two key provisions, which require insurers to take customers with pre-existing conditions, and to obligate insurers to consider young adults as children up to age 26 for the purposes of family healthcare plans.

"[I]t happens to be one of the strongest assets. Also with the [provision allowing] children living with their parents for an extended period. We're very much going to try to keep that. It adds cost, but it is very much something we're going to try and keep."

While some news outlets – including 60 Minutes – pounced on the comments, calling them a reversal from Trump’s pledge to repeal and replace, in fact Mr. Trump in the past made similar comments, suggesting that while he would rescind the ACA, he would seek to enact certain elements in a replacement law.

“I like the mandate,” Trump told Anderson Cooper on CNN in February, referring to the requirement that insurance companies take customers with pre-existing medical conditions. “I don’t want people dying on the streets.”

At a GOP primary debate Trump repeated his call to retain the mandate covering pre-existing conditions, saying he “would absolutely get rid of Obamacare,” but added that “I want to [the] keep pre-existing conditions [mandate].”