Radical preacher Anjem Choudary was charged on Wednesday with encouraging support for the Islamic State militant group.

Choudary, 48, appeared in Westminster magistrates court charged with inviting support for a proscribed organisation, namely Isis. It is alleged he committed the offence between 29 June 2014 and 6 March 2015. Another man, Mohammed Rahman, 31, faced the same charge.

It is alleged Choudary and Rahman publicised support for Isis and its leader Abu Bakr al-Baghdadi through lectures published online, the court heard.

Dressed in a white ankle-length robe, the married father of five, who lives in Ilford, told the court he wished to represent himself and pleaded not guilty to the charge.

Choudary, a trained solicitor who was previously chairman of the Society of Muslim Lawyers, appeared alongside Rahman who faces the same charge of inviting support for a proscribed terrorist organisation.

Asked how he would like to plea to the charges, Choudary said: “I plead that Cameron and the police are guilty and the only people who are innocent are me and Mr Rahman.”

Rahman, dressed in a blue hoodie, also pleaded not guilty.

District judge Howard Riddle, the chief magistrate, referred the case to the crown court and refused the men’s bail, remanding them in custody. Both are due to appear at the Old Bailey on 28 August.

In an earlier statement, Sue Hemming, head of special crime and counter-terrorism at the Crown Prosecution Service (CPS), said: “Following an investigation by the Metropolitan police’s counter-terrorism command, we have today authorised charges against Anjem Choudary and Mohammed Mizanur Rahman.

“We have concluded that there is sufficient evidence and it is in the public interest to prosecute Anjem Choudary and Mohammed Rahman for inviting support for Isil, a proscribed terrorist organisation, between 29 June 2014 and 6 March this year. Each man is charged with one offence contrary to section 12 of the Terrorism Act 2000.

“It is alleged that Anjem Choudary and Mohammed Rahman invited support for Isis in individual lectures which were subsequently published online.”

Choudary was one of the founder members of the Islamist group al-Muhajiroun which formed in 1996 under the charismatic leadership of Omar Bakri Mohammed.

The group held rallies and events which attracted hundreds of young Muslims and Choudary, who at one point trained as a lawyer, was appointed Bakri’s deputy. Soon after, he proclaimed himself a sharia scholar.

The Home Office banned the group in 2010. Choudary went on on to form several successor organisations such as al Ghurabaa and Islam4UK, which were also proscribed.

In the last year, he has been giving audio lectures on the internet through video chat site Paltalk, and quietly advertised through WhatsApp and on his Twitter feeds.