Turkey has plunged into a political crisis after the army threatened to intervene against the Islamist-rooted government on Friday night and up to 1 million people staged an anti-government rally in Istanbul on Sunday.
Turkey's financial markets tumbled on Monday and Europe and the United States called for a democratic resolution to the crisis while some commentators warned that the country was proving itself unsuitable for accession to the European Union.
The dispute between secularists led by the powerful army and the government has erupted over the ruling Justice and Development Party's (AKP) candidate for the presidency, Foreign Minister Abdullah Gül, a former Islamist whose wife wears the Muslim headscarf banned in universities and public offices.
Secularists fear that Prime Minister Tayyip Erdogan and Gül want to erode Turkey's strict separation of state and religion. Many protesters accused the government of planning an Islamist state and criticized it for failing to consult the opposition over its choice of president.
Turkey's military, which has toppled three governments since 1960, warned it may not allow a candidate with Islamist roots to be president. In an election on Friday in parliament where the AKP has a majority, Gul had come within 10 votes of being the first Turkish president with an Islamist past. A second ballot is due May 2.
Hours after the election, army generals issued a statement saying: "Arguments over secularism are becoming a focus during the presidential election process and the Turkish armed forces are following the situation with concern. It must not be forgotten that the armed forces are the determined defenders of secularism.''
Gül, 56, defied the warning and said he would remain his party's presidential candidate. Erdogan nominated Gül on April 24. Other possible candidates for president included Defense Minister Vecdi Gonul, who analysts said would have secured the military's support. The current president, Ahmet Necdet Sezer, is a staunch secularist and his term expires May 16.
Turkey's Constitutional Court began on Monday to examine an opposition request to suspend the presidential election, a move which would trigger parliamentary elections and, in the eyes of analysts, would help defuse tensions.
Erdogan, who has won praise in Europe for his liberal economic and social reforms aimed at bringing Turkey into the EU, denies any secret agenda and says he only wants to ease some of Turkey's curbs on religious expression. Analysts said the reforms have made Turkey more open and democratic and have diminished the army's capacity to interfere in politics.
The Council of Europe condemned the military's action. "I am very concerned about the recent public statement by the Turkish military. This statement looks like a deliberate attempt by the armed forces to influence the election of a new President in Turkey. They should stay in their barracks and keep out of politics," said Terry Davis, Secretary General of the Council of Europe, in a statement on Sunday.
"The Turkish people have achieved great progress in respect for Human Rights, democracy and the Rule of Law since Turkeys accession to the Council of Europe in 1949. These achievements should not be put at risk," he went on. "In a democracy, the military are under the command of democratically elected State authorities. The armed forces do not have any democratic legitimacy of their own and therefore cannot have a political role.
"I am shocked that the military in a member state of the Council of Europe should behave in this way in the midst of a democratic and constitutional process such as the election of the Head of State. I call on all political parties to take a clear stand against interference by the armed forces in the political process."
Erdogan said he would address the nation at 8:15 p.m. local time on Monday (5:15 GMT).
Officially, the Turkish president's duties are largely ceremonial and the post is regarded as less powerful than that of the prime minister. But the presidency, first held by the founding father of the modern Turkish Republic, Mustafa Kemal Atatürk in the 1920s, holds huge symbolic importance for Turks.
The president has limited constitutional powers, including the ability to veto legislation. That was done on a few occasions by current incumbent Sezer in response to AKP-driven bills.