[The] Turkish government's demands for a no-fly zone and a buffer zone in areas bordering Iraq and Syria, two key conditions for further engagement with the U.S.-led coalition against Islamic State (IS), have not been well received by most the country's partners and allies.
Turkish President Recep Tayyip Erdogan repeated the demands on Friday in Northeastern city Trabzon, saying that the fight against IS militants will fail unless ground offensive launched to complement air campaign.
He listed three conditions for Turkish involvement, namely the establishment of a buffer zone or safety zone; enforcing a no-fly zone over Syria to secure the opposition from Syrian regime's air assault; training and equipping moderate groups against the IS and regime forces.
However, the United States said it has never ruled out Turkey's buffer zone proposal, yet added that it is not considering to implement it at the moment.
"We're working with the Turks to identify and undertake actions that support our shared objectives in Syria and Iraq, and when they have ideas they raise them. And we're open to discussing this (buffer zone). We've never ruled it out. We're just not considering the implementation at this time," U.S. State Department Spokesperson Jen Psaki said on Wednesday.
Officials from the White House and U.S. defense department were not as diplomatic as the state department in ruling out buffer zone options for the moment.
"It (a buffer zone) is now not on the table as a military option that we're considering," said Rear Adm John Kirby, Pentagon 's press secretary.
White House spokesman Josh Earnest also told reporters on Wednesday that a buffer zone isn't under consideration.
Turkey's proposal is not a new idea and is not "on the front burner", Tony Blinken, U.S. Deputy National Security Adviser, said in London on Friday as well.
NATO's Secretary-General Jens Stoltenberg, who paid a visit to Turkey this week, said on Friday a no-fly zone and safe zone in Syria are not part of present NATO discussions. Speaking to Turkish daily Today's Zaman on Friday, Stoltenberg said the safe zone issue is "not on the agenda of NATO."