The 55-year-old businessman uploaded a video of himself wheeling a trolley with three boxes of diapers and two boxes of the pair's Casamigos Tequila through the office to mark the arrival of George and Amal's twins, Alexander and Ella.
Captioning the video, he wrote: ''Special delivery. #HouseOfFriends (sic)''
George and Amal announced they had welcomed a healthy baby boy and baby girl in a statement released by his publicist on Tuesday (06.06.17).
He said: ''This morning Amal and George welcomed Ella and Alexander Clooney into their lives. Ella, Alexander and Amal are all healthy, happy and doing fine ... George is sedated and should recover in a few days.''
Meanwhile, George previously claimed he and Amal, 39, had not yet decided on what they would call their children.
He admitted: ''No we haven't picked out any names and I'll tell you why ... Because I've had friends pick out names around their parents and then it becomes ... Whatever name you pick they're like, 'Oh, I don't like that. That guy's a prime minister' 'Can't name her Susan. You remember your Aunt Susan?'
''[But] can you believe it?! Yeah, [I'm] even happier [than before]. I didn't know that we'd have kids. I was very happy that we were going to get married and then [a pregnancy] seemed like the next step.''
And George revealed he and Amal have ''decided to be much more responsible'' after finding out they were expecting twins.
He said previously: ''We decided to be much more responsible, to avoid the danger. I will not go to South Sudan anymore and in the Congo, Amal will no longer go to Iraq and she will avoid places where she knows she is not welcome.
''Before, I did not care, I would even say that there was a pretty exciting side to going where no reporter had ever been. We have the chance to live between three countries: Italy, America and England.''
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