London: Madonna has vowed to use her upcoming concert in Russia`s St. Petersburg city to voice her support for local gays and campaign against a controversial bill banning same-sex propaganda.

The pop superstar is said to be disgusted by the new legislation, which outlaws reading, writing, speaking or reporting on anything related to gay, lesbian, bisexual or transgender issues, reports a website.

The bill that was signed into law last month threatens those who flout it with fines of up to USD 17,000.

Madonna is planning to test the ruling when she performs in St. Petersburg Aug 9.

"I will come to St. Petersburg to speak up for the gay community and to give strength and inspiration to anyone who is or feels oppressed," she said.

"I`m a freedom fighter. I don`t run away from adversity. I will speak during my show about this ridiculous atrocity."