"I have not seen my son in 14 years. I want to meet him. I want to hold him close to me, to my heart," the woman, introduced as Elena Skripal, told broadcaster Pervyi Kanal.
"I am 90 years old. I do not pose a danger to anyone. Please, let me just make a phone call to my son," she added, shown sitting in a nightdress.
"Why don't they allow a call? Why? For what reason? After all, when he was at home we talked every week... I demand he be allowed talk to me," she said tearfully to a talk show.
Skripal is a former military intelligence officer who passed information on Russia's agents in Europe to British security services, resulting in imprisonment in his homeland.
He moved to Britain as part of a spy swap deal in 2010 and has lived there ever since.
Skripal and his daughter Yulia, visiting from Moscow, were discovered unconscious on a park bench in the southern British city of Salisbury on March 4.
Yulia Skripal, who spent several years living in Britain before returning to Russia, was released from hospital on April 11.
Sergei Skripal left hospital last Friday more than three months after the poisoning, which Britain blamed on Moscow.
Russia has denied responsibility, calling the accusations "unsubstantiated".
The case sparked a diplomatic crisis that saw Russia and the West expelling dozens of diplomats in tit-for-tat moves.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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