Eight Nobel Peace Prize laureates on Monday sent a letter to the leaders of Spain and Catalonia to express their support for mediation to solve the conflict in Catalonia.

"We support the calls for mediation and negotiations toward a peaceful resolution of the current stand-off between the Spanish government and Catalonia," read the letter published on the website of the Nobel Women's Initiative, a group created in 2006 to promote collaboration among the laureates.

In the letter, the eight intellectuals do not specify any political leaders of Spain and Catalonia as recipients, although they said that a copy was sent to the European Commission.

The Nobel laureates condemned the violence on Oct. 1 in Catalonia and referred to the referendums held in Quebec and Scotland, regions where secession was voted against in 1995 and 2014 respectively, as examples of "mature democracies" and "freedom of expression".

Among the intellectuals who signed the letter were Argentinean Adolfo Perez Esquivel, a 1980 Nobel Prize laureate, Guatemalan indigenous activist Rigoberta Menchu, who received the Nobel Peace Prize in 1982, and former President of East Timor, José Ramos-Horta, a 1996 awardee. 

 Catalonia’s leader, Carles Puigdemont, will address the region’s Parliament today, possibly to declare independence from Spain.

The Spanish goverment considers the catalan law that called for a referendum, and the following declaration of independence, unconstitutional.