Catalan pro-independence organisation Òmnium Cultural has started a new campaign to call on the leaders of France, Germany and the United Kingdom, Emmanuel Macron, Angela Merkel and Boris Johnson, to get involved in finding a political solution to the Catalan conflict and for the release of the political prisoners.

The campaign, called Act for Catalonia, hopes to reach 10 million people, encouraging citizens of the three countries to petition their political leaders to "not look the other way" and "communicate to the Spanish prime minister the need to release the Catalan leaders and start a process of dialogue to find a political solution to the conflict between Catalonia and Spain".

The organisation has set up a website with sample emails and tweets in the relevant languages that can be automatically sent to the three leaders. They have emailed those who have already signed a petition they plan to send to the "Spanish government and the main European institutions".

To publicise the campaign, they have produced an advert with British actor Toby Harper which says that, in the face of the 2017 Catalan referendum, "the Spanish government opted for repression". It also notes that the UN Working Group on Arbitrary Detentions and Amnesty International have "called on Spain to release Catalan leaders", including Òmnium's president, Jordi Cuixart.

The sample letter says that Cuixart "will spend nine years in prison for exercising his human rights, such as freedom of expression and the right to protest." It adds: "In total, the Catalan leaders will have to spend 100 years in prison for supporting a referendum."

Next year, the campaign will be widened to explicitly include Belgium, Switzerland, Austria, Norway, Sweden, Denmark, Finland, Iceland and the Netherlands.