A demonstration against anti-gay laws introduced in Russia in June will take place in London tomorrow.

The Day of Action – Love Russia, Hate Homophobia – will take place on 3 September from 5-8pm opposite Downing Street on London’s Whitehall.

The rally takes place just two days before the G20 summit opens in the Russian city of St Petersburg. Organisers are calling on British Prime Minister David Cameron to urge Russia’s President Vladimir Putin to drop the law.

It is hoped the protest will increase pressure on the International Olympic Committee (IOC) to insist that Russia gives cast-iron assurances that LGBT competitors, spectators and members of the Russian public – and their straight allies – will not be victimised for supporting LGBT equality during the Sochi 2014 Winter Olympics.

Last month hundreds of people, including Stephen Fry, rallied opposite the gates of Downing Street in a show of solidarity with Russia’s LGBT community.

Human rights campaigner Peter Tatchell said: “There can be no normal sporting relations with an abnormal authoritarian regime like Putin’s Russia. The attack on the LGBT community is one fragment of a much wider attack on human rights.”

“It is important to encourage an alliance between LGBT and straight Russians to defend freedom of expression for all the people of Russia. LGBT people need allies to win and all Russians who love democracy and human rights deserve our support.”

QX magazine editor Cliff Joannou said: “In June this year, Russia’s President Vladimir Putin signed into law legislation that effectively bans any positive discussion, debate or portrayal of LGBT people and relationships. Gay athletes and spectators attending the Winter Olympics could potentially face fines and/or jail sentences merely for coming out or affirming their support for LGBT equality.

“The International Olympic Committee Charter prohibits any form of discrimination. It cannot carry on as if no human rights abuses are happening in Russia and as if these abuses will not impact on the Winter Olympics.”

“There have been protests in countries across the globe over the past few weeks against Putin’s legislation, including in London on 10th August.”

“It was the huge response to this event that gave me the idea that what was needed was for LGBT communities around the world to come together on one day with a single voice against Russia’s anti-gay policies and to demand that their own governments take action to press for an end to Russia’s anti-gay law.

“This is particularly relevant and urgent, given that Russia currently holds the presidency of the G20 and will be hosting the G20 summit on 5th and 6th September.”

He added: “With this Day of Action we are calling on people in Britain and around the world to join us in a unified, coordinated global protest. We are not asking for the 2014 Winter Olympics to be cancelled, but Russia’s homophobic discrimination needs to end and we need action by the IOC to help make sure this happens.”

President Vladimir Putin signed the law in June banning the promotion of “non-traditional relationships” toward minors, a move that has been criticised as part of a broader crackdown on Russia’s gay community. Other laws banning the adoption of Russian children by foreign same-sex couples, and one which enables organisations receiving funding from abroad to be fined as “foreign agents”, were also passed.

Out4Russia, launched last week and allows users to lobby G20 governments into action against the Russian law.