Hillary Clinton, US secretary of state, will lend her support to Turkish and Armenian efforts to end one of the most intractable conflicts in the Caucasus when the two countries sign agreements on Saturday to mend diplomatic relations and open their shared border.
Mutual animosity is rooted in the 1915 massacres by Ottoman Turks of up to 1.5m Armenians. Turkey also closed its border with Armenia in 1994 to support its ally Azerbaijan in a conflict with Armenia over the disputed territory of Nagorno-Karabakh.
If the agreement comes into effect, it will be a triumph for Turkey, increasingly active in regional diplomacy and keen to be seen as a force for stability in the Caucasus. But it also reflects the importance the US attaches to ending frozen conflicts in a strategically important region, the corridor for bringing Caspian oil and natural gas to the west.
Barack Obama, addressing the Turkish parliament in one of his first overseas visits as US president, called for “peaceful and prosperous coexistence” between the two countries.
Mrs Clinton has urged both sides to follow through on an agreement that could still fall victim to determined public opposition.
The ceremony in Zurich reflects a year of careful diplomacy since Abdullah Gul, Turkish president, launched the rapprochement by attending a football match in Yerevan between the national sides. Serzh Sargsyan, his Armenian counterpart, is likely to travel to Turkey for the return fixture, to be played on Wednesday.
The protocols fix a timetable for re-establishing diplomatic relations, opening the border and establishing a commission to build economic ties and handle the historical debate.
Government sources in both Ankara and Yerevan confirmed the agreement would be signed, but could not say when the protocols might be sent to parliament for ratification.
Although landlocked Armenia would benefit economically from opening the border, Mr Sargsyan has to convince wealthy diaspora communities he is not abandoning Armenian demands for Turkey to recognise the 1915 killings as genocide. He faced fierce protests this month during visits to Lebanon, France and the US.
Resolving the conflict would smooth Turkey’s path to European Union membership and remove an irritant from its relationship with the US, whose Armenian community has long pressed for genocide recognition from legislators.
The protocols set a deadline of two months from ratification for opening the border, but Recep Tayyip Erdogan, Turkish premier, has promised Azerbaijan not to do so without addressing Azeri grievances over Nagorno-Karabakh.
Diplomats said talks between Mr Sargsyan and Ilham Aliyev, Azeri president, paved the way for Saturday’s ceremony.
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