Oslo (dpa) - The Tunisian National Dialogue Quartet was handed the 2015 Nobel Peace Prize in Oslo on Thursday and praised for its "resolute action" to stop the spiral of violence.The alliance of trade unions, employers organizations, human rights groups and lawyers was honoured for its role in upholding democracy and the peaceful political process in the North African nation.The National Dialogue Quartet was founded in 2013 when Tunisia‘s transition to democracy was threatened with collapse."The resolute action of the quartet contributed to ending the spiral of violence and placing events on a favourable course," said the head of the Nobel jury, Kaci Kullmann Five.Norwegian Foreign Minister Borge Brende expressed hope that the achievements in Tunisia would serve as inspiration to other countries in the Middle East which want to develop further.Later, King Carl XVI Gustaf of Sweden was due to present the other Nobel prizes for literature, medicine, physics, chemistry and economics to the winners in Stockholm.The awards, each worth 8 million Swedish kronor (960,000 dollars), were bequeathed by Swedish industrialist and dynamite inventor Alfred Nobel and are presented each year on the anniversary of his death.The quartet comprises the Tunisian Human Rights League, the Tunisian General Labour Union; the Tunisian Confederation of Industry, Trade and Handicrafts; and the Tunisian Order of Lawyers.Tunisia was the first in a string of countries in North Africa and the Middle East to rise up against longtime, autocratic rulers in 2010 and 2011. It is also widely seen as the sole success story of those popular revolts, dubbed the Arab Spring.But the peace process in the country has suffered setbacks since the peace prize was announced in October.A suicide attack on the presidential national guard at the end of November forced the authorities to declare a state emergency. The country is also facing severe economic and social problems.Two quartet members representing the employers and trade unions are locked in a bitter pay dispute, resulting in them travelling separately to Oslo for the awards ceremony.The Nobel Prize for Literature will be presented to Ukraine-born Svetlana Alexievich and the medicine award to William C Campbell and Satoshi Omura for their work on a therapy against infections caused by ringworm parasites.Takaaki Kajita and Arthur B McDonald are to receive the physics award for their discoveries of neutrino oscillations while Tomas Lindahl, Paul Modrich and Aziz Sancor are being honoured with the chemistry prize for their studies of DNA repair.The economics award will be presented to Angus Deaton for his work exploring the interrelationship of consumption, poverty and welfare.