The presidents of Turkey and Armenia will build on recent moves to end a century of enmity when they attend a World Cup football qualifier between their teams on Wednesday.

Turkish President Abdullah Gul attended the initial game in Armenia last year. The so-called "football diplomacy" contributed to the signing this past weekend of an agreement to establish diplomatic ties and open their border within two months.

The agreement needs to be approved by the parliaments of both countries. The deepest dispute is over history and has yet to be resolved: Armenia and many historians allege Ottoman Turks committed genocide against Armenians early in the last century, a charge that Turkey denies.

But the two sides will focus on goodwill at the football game, though security will be tight for fear of protests from Turkish nationalists who oppose reconciliation. Both teams have been knocked out of the competition, so suspense over the score will be lacking.

"I call on the fans to ignore any provocation that might come from people who desire to abuse the process between Turkey and Armenia," Turkish Prime Minister Recep Tayyip Erdogan said Tuesday.

Armenian President Serge Sarkisian has said he will attend the game in Bursa, a former Ottoman imperial capital.

The agreements have strong support in the two countries' parliaments, but face stiff opposition from nationalists. Turkey has said it would send the agreement to parliament next week.

"We have paved the way for a solution in our capacity as the government, but the parliament indeed has the power to say the last word on this issue," Erdogan said.

The agreement was signed after a last-minute hitch was solved by U.S. intervention, illustrating the difficulties still ahead.

A day after the deal was signed, Erdogan repeated a demand that Armenia withdraw from disputed enclave of Nagorno-Karabakh. Armenia controls the enclave in Azerbaijan, which is inhabited mainly by ethnic Armenians. Turkey sealed its border with Armenia in response to the country's invasion of Nagorno-Karabakh in 1993, in a show of solidarity with ally Azerbaijan.

Azerbaijan, a regional oil and gas power, has criticized the deal, saying it aggravates the Nagorno-Karabakh conflict.

The deal also faces opposition from the powerful Armenian diaspora, which insists that Turkey accept that the killing of up to 1.5 million Armenians during the final days of the Ottoman Empire amounts to genocide. Turkey says the number is inflated and that many died on both sides during a chaotic period.

That contentious issue is only hinted at in the agreement, which calls for a commission to be set up to study the issue.

Police stepped up security in Bursa, in northwestern Turkey. Authorities have urged soccer fans to refrain from acts of nationalist fervor in the stadium. Earlier this month, fans of the local team, Bursaspor, chanted nationalist slurs against supporters of Diyarbakirspor, a team from the predominantly Kurdish southeast.

Turkey won the first game against Armenia in Yerevan in September 2008 by a score of 2-0.