BAKU (AFP) -- Azerbaijan on Sunday slammed its ally Turkey for agreeing to normalize ties with Armenia and warned that the opening of the Armenian-Turkish border could cause instability in the volatile South Caucasus.

“The normalization of relations between Turkey and Armenia before the withdrawal of Armenian forces from occupied Azerbaijani territory is in direct contradiction with the interests of Azerbaijan and casts a shadow over the spirit of brotherly relations between Azerbaijan and Turkey, built on deep historical roots,” the Azerbaijani foreign ministry said in a statement.
“Azerbaijan believes that the unilateral opening of the Turkish-Armenian border calls into question the architecture of peace and stability in the region,” it added.
Armenian Foreign Minister Eduard Nalbandian and his Turkish counterpart Ahmet Davutoglu on Saturday signed landmark pacts to normalize their two countries' relations and open their shared border.
The deals, which must still be ratified by the two countries' parliaments, are a first step to reconciliation after nearly a century of bitterness over World War I-era massacres of Armenians under Ottoman rule.
Azerbaijan has strongly objected to Turkey normalizing ties with Armenia and opening the border before the resolution of Baku's conflict with Armenia over the disputed Nagorny Karabakh region.
Backed by Yerevan, ethnic Armenian separatists seized control of Nagorny Karabakh and seven surrounding districts from Azerbaijan in the early 1990s, in a war that claimed an estimated 30,000 lives.
Turkey closed its border with Armenia in 1993 in solidarity with Azerbaijan over the conflict.
Armenia has rejected any linkage between the conflict and its reconciliation efforts with Turkey.
Armenia and Azerbaijan have cut direct economic and transport links and failed to negotiate a settlement on the status of Nagorny Karabakh despite years of talks.
Armenian and Azerbaijani forces are spread across a ceasefire line in and around Nagorny Karabakh, often facing each other at close range, and shootings are common.