Claiming that Soofiya was a victim of conspiracy, Madani told mediapersons at Anvarassery near Kollam that he would hold the fast in Thiruvananthapuram.
"I will continue my struggle till my family's innocence is proved before the conscience of Kerala... We are victims of a plot hatched by a section in the police and their political overlords," Madani, flanked by his aged parents, said.
His 13 and 11 year old sons would join him in the fast, Madani, whose acquittal in the 1998 Coimbatore bomb blast was upheld by the Madras High Court on Friday, said.
He described as 'baseless' reports that his wife had admitted to her involvement in the bus burning incident in September 2005 during a protest against his detention then in connection with the Coimbatore blasts that left 58 persons dead and over 200 others injured.
"This is misinformation being fed by police to the media to malign me and and my family to create misgivings in people's minds," he said.
A two-member Tamil Nadu police team questioned Soofiya in Kochi on Friday in connection with the planned bomb attack on the Coimbatore Press Club in 2002 before she was produced in a court, which remanded her to judicial custody in the bus burning case
Soofiya, arrested on Thursday, has been listed as the tenth accused in the case recently after the arrest of suspected Lashkar-e-Tayiba militant T Naseer, with whom she had alleged contacts over phone.
A two-member Kerala police team would be leaving for Tamil Nadu next week to gather evidence from prison officials and inmates of Coimbatore jail where Madani was lodged after the Coimbatore blasts.
Police said the team would collect evidence regarding various calls received and attended by Madani.
They would also try to ascertain if Madani was aware of the Tamil Nadu bus burning incident in which suspected LeT Operative Naseer was the main accused.
Another accused K Nasir has filed a petition in the Kerala High Court seeking anticipatory bail. The petition is likely to come up before the court on Monday.