"My understanding is ... we haven't had a formal request of NATO" for the U.S.-built missile system for Turkey, State Department spokeswoman Victoria Nuland told reporters on Tuesday.
"We will await a formal request, and then NATO will deliver aid. But, we're obviously looking at the full range of things to ensure that Turkey remains safe and secure," she added.
Nuland's comments run contrary to reports out of Ankara claiming a weapons request is being drafted by the Turkish Foreign Ministry for NATO, according to reports in the region.
"Everything will be considered within the framework of possible preparations," Turkish Foreign Minister Ahmet Davutoglu told state-run Anatolian news agency regarding the request.
Negotiations between Brussels and Ankara over potential military support has ramped up in recent months, as the growing civil war in Syria has already begun to boil over into Turkey.
For nearly a year, government troops and paramilitary forces loyal to Assad have battled their way to a bloody stalemate with rebel fighters looking to oust the longtime leader.
In October, Turkish lawmakers took the controversial step of authorizing military action inside Syria after forces loyal to Syrian president Bashar Assad launched a mortar attack against targets inside Turkey.
Turkish Deputy Prime Minister Besir Atalay told the Associated Press that Ankara's decision should not be interpreted as an act of war against Syria.
Shortly after the cross border attack, Turkey Prime Minister Tayyip Erdogan met with NATO leaders to discuss possible action by the alliance against Assad's forces under Article 4 of the NATO charter.
Article 4 requires consultations with all NATO members when a partner nation feels its "territorial integrity, political independence or security" is being threatened by an outside country.
Since those talks, the United States, NATO and Turkey have continued "to look at what other defenses [or] support Turkey might require," according to Nuland. Options which may include deployments of Patriot systems.
To that end, Russian Foreign Minister Sergei Lavrov told reporters that members of the Free Syria Army (FSA), the largest rebel faction in the country, had upwards of 50 American-made Stinger surface-to-air missiles in their arsenal.
The Stingers, which have reportedly been used to take out Syrian fighter jets above the rebel stronghold of Aleppo, could also be used to take out civilian aircraft, Lavrov told reporters during a press conference in Jordan on Tuesday.
"The leaders of the [FSA] have repeatedly said that civilian planes will be a legitimate target," according to Lavrov.
Russia has been one of the strongest international supporters of the Assad regime during the conflict, sending troops and weapons to Damascus since the early days of the civil war.