Mursitpinar: Kurdish fighters engaged in fierce clashes with jihadists on the Turkish border near Kobane on Monday, as Ankara denied allowing Washington to use its bases against the Islamic State group.
US officials had earlier said Turkey would also host training for "moderate" Syrian rebels, in the hopes of finally creating a force capable of tackling IS on the ground.
"There is no new agreement with the United States about Incirlik," a Turkish government official told AFP of an air base in southern Turkey that the US wants to use to launch air strikes.
"Negotiations are continuing" based on Turkish conditions previously laid out, the official added.
Near Kobane, fighting spread early today to the border area just north of the flashpoint town, threatening to cut it off from the outside world.
IS fighters were also putting strong pressure on pro-government forces in Iraq, with concern over Anbar province and the key oil refinery of Baiji.
With the jihadists advancing on its doorstep, NATO member Turkey has come under intense pressure to take action as part of a US-led coalition that has been carrying out air strikes in Syria and Iraq.
US officials said Turkey had agreed to let Washington use its bases including Incirlik for the air campaign.
Pentagon chief Chuck Hagel said the agreement included "hosting and conducting training for Syrian opposition members" in Turkey, noting that Ankara would welcome a US Command team next week to "develop a training regimen".
US military planners have repeatedly warned that the air campaign alone will not be enough to defeat IS, which in June declared an Islamic "caliphate" in the large parts of Syria and Iraq under its control.
Turkish Prime Minister Ahmet Davutoglu yesterday called for military backing for Syria's "moderate opposition" to create a "third force" in the war-torn country to take on the Damascus regime as well as IS militants.
Near Kobane, clashes with automatic gunfire and mortar fire were taking place less than a kilometre (half a mile) from the barbed wire fence that marks the border between Syria and Turkey, an AFP reporter on the Turkish side said.
Turkey had moved reinforcements to the border including more tanks and self-propelled artillery, the reporter said.
The US-led international coalition launched at least two new air strikes against IS positions in the area, with one striking the heart of the town and sending a huge plume of smoke skywards.
Kobane has become a highly visible symbol of resistance to IS and its fall would give the jihadists control of a long stretch of the Turkey-Syria border.