Turkey and Armenia are set to sign a landmark accord Saturday tonormalize relations and end a century of bitterness over the World WarOne killings of Armenians under Ottoman Turkish rule.

TheArmenian and Turkish foreign ministers, Edward Nalbandian and AhmetDavutoglu, are expected to sign protocols in Zurich, Switzerland torestore diplomatic ties and open the countries' sealed border.

US Secretary of State Hillary Clinton (file photo)U.S. Secretary of State Hillary Clinton and Russian Foreign Minister Sergei Lavrov are due to attend the ceremony.

Theagreement must be ratified by the Armenian and Turkish parliaments, butanalysts say strong domestic opposition in both countries will likelyslow the process.

Turkey and Armenia have been locked in anearly century-old dispute over the mass killing of Armenians byOttoman Turks during and after World War One.  Armenians want themassacres recognized as genocide - a label Turkey strongly rejects.

Some 10,000 protesters marched against the agreement in the Armenian capital, Yerevan, on Friday.

Theagreement calls for a joint commission of independent historians toexamine the genocide issue, which some experts say is a concession toTurkey since the panel will reopen an issue Armenia says has alreadybeen confirmed.

An ongoing territorial dispute between Armeniaand Turkey's ally, Azerbaijan, could also complicate efforts tonormalize Armenian-Turkish relations.

Turkey closed its borderwith Armenia in 1993 in solidarity with Azerbaijan, which was fightingArmenian-backed separatists in Azerbaijan's breakaway Nagorno-Karabakhterritory.

Azerbaijani President Ilham Aliyev said Friday thattalks with his Armenian counterpart, Serzh Sarkisyan, over the disputedenclave had failed, contradicting previous statements by Russia.

Thetwo presidents discussed the issue Thursday in the Moldovan capital,Chisinau, during a summit of the Commonwealth of Independent States, agroup comprised of most of the former Soviet republics.

Some information for this report was provided by AFP and Reuters.