Matt Damon has shared the unusual reaction he had when friend George Clooney revealed that he and wife Amal were expecting twins.

Damon said he first found out the exciting news last fall, when Amal was just eight weeks pregnant, and his immediate reaction was to remind his friend about the ’12-week rule’ when it comes to sharing pregnancy news.

Matt DamonMatt Damon knew about The Clooney’s baby knew before anyone else

Speaking to Entertainment Tonight Canada, Damon said: “I was working with him last fall and he pulled me aside on set and I mean, I almost started crying. I was so happy for him. And I was like, ‘how far along is she?’ And he goes, ‘eight weeks.’”

The actor said he then told his friend: “‘Are you out of your mind?! Don’t tell anybody else! Don’t tell anybody else! Don’t you know the 12-week rule?’ Like of course he doesn’t. I was like, ‘just shut up, man.’ Then four weeks later, 'I'm like, 'We're good right, we're good,' so I'm thrilled for him.

“She’s amazing,” Damon added. “He hit the jackpot. Just on every level. She is a remarkable woman. They’re gonna be great. They’re gonna be awesome parents. Those kids are lucky.”

More: It's Official! Amal Clooney Is Pregnant With Twins

Clooney’s mother Nina has also been sharing her joy at the news, which she revealed her son delivered to her and husband Nick in person. “We are extremely happy for George and Amal, and I cannot imagine two people who would be better parents,” Nina told US Weekly.

“We were with them and they told us together. We were all together, and it was lovely. It was just a personal moment. I think he’ll be great, and I think she’ll be a great mom!” she added.

George and Amal’s news was confirmed on Thursday by friend Julie Chen on 'The Talk'. During the show Chen announced: "Beyoncé is not the only superstar expecting twins. Congratulations are in order for George and Amal Clooney!”.