Nick and Nina, who are already grandparents to daughter Adelia's two grown-up kids, hope to eventually meet the newborns in person once George and Amal settle into life as parents, but they are in no rush.
Nick said he is head-over-heels in love with his "perfect" grandchildren who he described as "absolutely beautiful".
"George will be an absolutely wonderful father".
"Really well and Amal, who is Superwoman, she is just incredible and she was guiding the narration", he told Cincinnati's FOX 19 in a telephone interview.
Considering Amal's illustrious career and history as an attorney of global law, she is doing just how you would expect. George, well, his eyes were glazed so I'm not sure that he was sober!'
George Clooney will be a 'wonderful' parent says his father as he jokes his son 'married up' with Amal
"She was telling us last week that she is as big as a house", he told Cincinnati WXIX anchor Tricia Macke in a phone interview. Swinton said she shared very little. But as Nick concluded in his video message to Good Morning Britain, the couple is "very grateful" for all the well-wishes and support they have received from their fans over the past few days.
"Now that's a joke".
"But by golly, when we met Amal, we got that figured out in a hurry".
George and Amal married in 2014 in a ceremony in Italy. "I did and so did he".
"They are gorgeous. Nina swears they have George's nose".
"I've just laughed. I've laughed at him across the airwaves", she said of her Hail, Caesar costar.
Inspirational Djokovic key to my tennis return - Agassi
Whatever is practical and achievable, 100% I will make the effort. Novak Djokovic with coach Andre Agassi at the French Open .