ANKARA (AFP) - President Abdullah Gul on Saturday becomes Turkey's first head of the state to visit Armenia, but his bid to ease relations with a historic foe that accuses Turks of genocide has angered nationalists. Gul will go to Yerevan to watch a football match between the two countries, which do not have diplomatic relations and remain deeply divided after the World War I. "A visit around this match can create a new climate of friendship in the region," the Turkish presidency said in a statement. This is a qualifying match for the 2010 World Cup finals and Armenia's President Serge Sarkisian invited Gul last month to attend. While some in the Turkish media have hailed the visit as historic and a potential breakthrough, the trip remains highly controversial. Amid a wave of opposition criticism, the ruling Justice and Development Party (AKP), which Gul belonged to before being elected president last year, adopted a very cautious tone. "I think it is very positive that the president is going. Rejecting the (Armenian) invitation would have meant sacrificing sports to politics," Prime Minister Recep Tayyip Erdogan said in televised remarks. State Minister Mehmet Aydin appeared to acknowledge the political significane of Gul's move. "The facts that we have do not support the theory that the visit will resolve all the problems, but it is not right to assume that nothing will come of it either," Aydin was quoted by the Anatolia news agency as saying. Turkey's main opposition party said Gul's decision would send the wrong signal to Armenia over its campaign for the deaths of Armenians in 1915-17 to be recognised as "genocide". Armenia says up to 1.5 million people were killed in orchestrated massacres during World War I as the Ottoman Empire fell apart before being dismantled in 1920. Turkey rejects the genocide label and argues that 250,000- 500,000 Armenians and at least as many Turks died in civil strife as Armenians fought for independence in eastern Anatolia and sided with invading Russian troops. "Armenia does not recognise Turkish borders and accuses Turkey of having carried out genocide," said Mustafa Ozyurek of the main opposition Republican People's Party. "This step will only serve to encourage the opposing party," he said, referring to Armenia. The vice president of the MHP nationalist party, Tunca Toskay, called the visit "totally unjustified while the Turkish people are unjustly accused through lies of having committed genocide and while Armenia shows no sign of renouncing its policy in this respect." The trip, which comes amid heightened tensions in the Caucasus region following the conflict last month between Georgia and Russia, will only last a few hours, a Turkish diplomatic source said. But some Turkish media said it could be enough to begin real change in relations between the nations, comparing it to the "ping-pong diplomacy" between the United States and China in the 1970s.