Amal and George Clooney have announced the birth of twins – a boy and a girl – the first children for the international human rights lawyer and her movie star husband.

Amal Clooney and the Oscar-winning star of films like Ocean’s Eleven and Three Kings married in Italy in 2014, making them one of the world’s biggest celebrity couples.

“This morning Amal and George welcomed Ella and Alexander Clooney into their lives. Ella, Alexander and Amal are all healthy, happy and doing fine,” publicist Stan Rosenfield said in an email Wednesday morning AEST.

He added cheekily, “George is sedated and should recover in a few days.”

It is understood the babies were born in a London hospital. The couple have been spending much of their time recently in England, where they have one of several homes.

People magazine reported on Tuesday that former US President Barack Obama visited the Clooneys at their home in the countryside west of London on May 27.

Amal Clooney, 39, and George Clooney, 56, adopted a low profile during her pregnancy, keeping the news private for months before it was confirmed in February by the actor’s close friend, Matt Damon.

Since then, the couple, who have homes in England, Italy and the United States, have said little about the pregnancy.

Amal Clooney has largely continued her work as a human rights lawyer, addressing the United Nations in March and urging the international community to investigate crimes committed by Islamic State in Syria and Iraq.

George Clooney cancelled a visit to Armenia for a humanitarian event this past weekend, saying in a message to organisers that “if I came there and my wife had twins while I was there, I could never come home”.

On Tuesday, social media lit up with congratulatory messages. “Ella and Alexander” was among the top trending topics on Twitter in the United States.

– With AAP