Fahmy, who holds dual Canadian-Egyptian citizenship, has been granted a retrial, the journalist said in the statement.
"The trial date on February 12 represents our worst nightmare, to have to go through another circus of a retrial," he said.
Fahmy was one of three Al Jazeera journalists arrested in Cairo in December 2013 and accused of being part of the country's banned Muslim Brotherhood, reported CNN online.
Producer Baher Mohamed, who is Egyptian, also remains behind bars.
Last week, Clooney said in a statement regarding Fahmy, who also used to work for CNN.
"I have been in touch with the Fahmy family and we are all delighted that Peter Greste has been released," it said, adding, "As Mr Fahmy's counsel we are doing all we can to ensure the same outcome for Mr Fahmy, who has suffered the same injustice.