LGBT activists in Russia have started a legal complaint against one of the lawmakers behind the country’s anti-gay ‘propaganda’ bill, which was approved unanimously by the State Duma on Tuesday.

Russia Today reports that LGBT activist and lawyer Nikolai Alekseev has called for sentencing against Yelena Mizulina, one of the key sponsors of the bill which seeks to impose a hefty fine for anyone “promoting the distorted understanding of social equality of traditional and non-traditional sex relations”.

Alekseev, the organiser of Moscow Pride, told the Izvestia paper that activists had made a complaint to the Prosecutor General’s office.

“Mizulina should be jailed for infringing minorities’ rights and inciting hatred for those who have non-traditional orientation. Millions of people suffer because of her actions,” he said.

Mizulina, the chair of the Lower House Committee for Children, Women and Family, said in defence: “Our bill has a very particular objective – to put a barrier between children and illegal information. People are not annoyed by gays, they are annoyed by unsolicited and emphatic promotion, by propaganda.”

Although she is one of the main sponsors of the bill, Mizulina is only one of many supporters in government. On Tuesday the Duma voted 436-0 with one abstention to pass it. The complete lack of opposition in parliament is a grim signal to Alekseev and his fellow activists.

The bill will move to a vote in the Upper House, which it will almost certainly pass, before being signed by into law President Vladimir Putin.

It originally banned “homosexual” propaganda specifically, but this was changed to “non-traditional sex relations” after criticism.

Promoting non-traditional sex relations could warrant fines of 4,000-5,000 rubles (£85-105) for individuals, 40,000-50,000 rubles (£850-1050) for officials, and 400-500,000 (£8,500-10,500) rubles for businesses.

The passage of the bill through the Duma has been marred by ongoing conflict between LGBT activists and the bill’s supporters.

The international community and human rights groups have been highly critical of the bill, with German Chancellor Angela Merkel among the most recent figures to speak out against it.

International Relations Minister Aleksey Pushkov tweeted in response to Merkel’s comments: “This call will not be heard. An acute conflict of values is looming.”

On Tuesday the Duma also passed a bill to make it a criminal offense to insult the feelings of religious believers, with punishments of compulsory labour, up to three years in prison, and/or fines of up to 500,000 rubles (£10,000).