* Some U.S. lawmakers have suggested no-fly zone
* Prime minister warns Syria has used chemical weapons
Prime Minister Tayyip Erdogan said Turkey would support a U.S.-enforced no-fly zone in Syria and warned that Damascus crossed President Barack Obama's "red line" on chemical weapons use long ago, according to an NBC News interview released Thursday.
A no-fly zone to prohibit Syrian military aircraft from hitting rebel targets has been mentioned by American lawmakers as one option the United States could use to put pressure on Syrian President Bashar al-Assad.
"Right from the beginning ... we would say 'Yes," Erdogan said when asked if Turkey, a NATO member that shares its longest border with Syria, would support such action, according to an NBC.com report.
But setting up a no-fly zone would require U.S. air strikes, and possibly forces sent into Syria, at the risk of casualties. There is little chance the United States would undertake that anytime soon, U.S. security officials say.
Still, Erdogan's comments could add pressure on Washington to take action in a two-year revolt that has killed 70,000 people and further destabilized a volatile region.
Erdogan also said Assad has fired missiles with chemical weapons at his opponents, crossing Obama's so-called red line a "long time ago."
Obama said in August he views the use of chemical weapons in Syria as a "red line." But, wary of the false intelligence used to justify the 2003 war in Iraq, the United States says it wants proof before taking any action.
"It is clear that the regime has used chemical weapons and missiles. They used about 200 missiles, according to our intelligence," Erdogan said in the interview with the U.S. television news outlet.
The Turkish leader did not make clear whether Turkey believed that all 200 missiles carried chemical weapons and said his government had not determined whether sarin gas was used.
"There are different sizes missiles. And then there are deaths caused by these missiles. And there are burns, you know, serious burns and chemical reactions," Erdogan told the network when asked what evidence Turkey had.
"And there are patients who are brought to our hospitals who were wounded by these chemical weapons," he added.
"You can see who is affected by chemical missiles by their burns," said Erdogan, who told NBC that Turkey would share intelligence with the United Nations Security Council.
Obama is set to meet with Erdogan in Washington on May 16.
Assad's forces and opposing rebels have accused each other of using chemical weapons. Erdogan told NBC he doubted Assad's opponents have used such weapons because they lacked access to them.
Turkey's state-run Anatolian news agency said earlier on Thursday that the country has sent eight experts to the border with Syria to test wounded victims of the country's civil war for traces of chemical and biological weapons.