Luis Moreno-Ocampo, the International Criminal Court (ICC) chief prosecutor, asked the court last month to issue an arrest warrant for al-Bashir on charges of genocide, war crimes and crimes against humanity in Darfur.
Asked about the possibility of an ICC warrant being issued while al-Bashir was in Istanbul, a Turkish foreign ministry official declined to speculate on what Turkey would do.
"Bashir was invited to the summit as an African country leader and there is no arrest warrant against him at his moment. If there are any requests, we will evaluate them then," the official said.
Even if an arrest warrant was issued while he was in Turkey, it would be highly unlikely that Turkish authorities would arrest him because the country has not signed the court's treaty and is not bound by its provisions.
However, Ankara is under pressure to become a member as part of negotiations to join the European Union
ICC judges could take weeks or months to issue a warrant, but have never failed to issue one after it was requested by the prosecutor.
The court returned from recess on Monday.
Diplomatic meetings
Moreno-Ocampo said al-Bashir's state apparatus had directly killed 35,000 people and indirectly led to the deaths of at least another 100,000.
International experts estimate about 200,000 people have died and 2.5 million have been driven from their homes since mostly non-Arab fighters took up arms in early 2003 accusing the central government in Khartoum of neglect.
Sudan blames the Western media for exaggerating the conflict and puts the death toll at 10,000.
The US-based Human Rights Watch organisation said on Friday it was "concerned" by Turkey's decision to welcome al-Bashir.
He is expected to hold bilateral meetings with Abdullah Gul, the Turkish president and Recep Tayyip Erdogan, the prime minister, on the sidelines of a summit which will focus mostly on energy and trade.
"The Turkish government should reject efforts by Sudan's president Omar Bashir to secure a suspension of the International Criminal Court's investigation against him," Human Rights Watch said in a statement.
"Turkey should also convey a clear message that Khartoum must not respond to the investigation with retaliation against civilians, peacekeepers, or humanitarian workers."
Energy interests
The summit is being hosted to help energy-thirsty Turkey tap into the African continent's vast resources.
Turkey, which has signed liquefied gas agreements with Algeria, is seeking to boost investments and trade with sub-saharan Africa, following similar moves by China and India.
Turkey has 12 embassies in the continent and plans to increase the number to 27 through next year.
"In recent years the continent became the focus of attention of several countries like China, India and Japan because of its rich energy and mining resources," a Turkish foreign ministry official said.
"It is Turkey's obligation to increase deals with Africa from the perspective of historical ties and fulfilling the potential of the continent."