"Today I want to make it absolutely clear to Assad and those under his command: The world is watching," Obama said.
"The use of chemical weapons is and would be totally unacceptable and if you make the tragic mistake of using these weapons, there will be consequences and you will be held accountable," he warned.
Several hours before Obama’s warning, White House press secretary Jay Carney said that the US was extremely worried by the possibility that Assad would use the chemical weapons at his disposal. Carney added the use of such weapons would definitely force the US to take action, without specifying what that action would entail.
Earlier, during her trip to Prague, US Secretary of State echoed the warning and said the use of chemical weapons would constitute the crossing of a red line for the US.
“Once again we issue a very strong warning,” she said, referring to Assad.
Meanwhile, Al Jazeera reported that according to AFP, an unnamed US official claimed the regime has already begun mixing chemicals that can be used to make deadly sarin gas.
"We've picked up several indications which lead us to believe that they're combining chemical precursors," the anonymous source is reported to have said.
It is worth mentioning that experts think that Syria is believed to have hundreds, if not thousands, of tons of chemical agents, including mustard gas, a blistering agent and the more lethal nerve agents sarin and VX.
In related news, NATO Secretary General Anders Fogh Rasmussen told reporters after a ministerial meeting of 28 NATO members in Brussels that NATO allies approved Tuesday the deployment of Patriot air defense systems in Turkey along the border with Syria.
“We stand with Turkey in the spirit of strong solidarity,” Rasmussen said.
“To anyone who would want to attack Turkey, we say, 'Don't even think about it!'" Fogh Rasmussen said as an implicit warning to Syrian regime.
Russian has warned Turkey that the NATO deployment of Patriot missiles along its border with Syria could spark a broader conflict.
"As they say, if a gun is hung on the wall at the start of a play, then at the end of the play, it will definitely fire," Putin said, after meeting Turkish Prime Minister Recep Tayyip Erdogan.
On the ground, SANA news claimed Tuesday that terrorists fighting against the regime fired a mortar on a school near the capital, Damascus, killing at least 28 students and one teacher.
"In a horrific crime, at least 28 students and one teacher were killed in Bteiha school in the Wafideen camp near Damascus. They were killed by a mortar launched by terrorists," said pro-regime Al-Mayadeen TV.
In response to school's attack, SANA news later reported that government forces killed multiple terrorists in the region, adding four Syrian troops were also killed in the clashes.
Furthermore, regime television said an armed terrorist group assassinated the journalist Naji Assaad in the Tadamun district of Damascus as he was on his way to the Tishreen newspaper.
In a new development, the European Union has decided to pull its diplomatic staff in Damascus, just hours after the UN said that he decided to withdraw all non-essential international staff from Syria because of security concerns.
"The UN has decided to send all non-essential international staff out of Syria and to halt all field trips outside of the capital for now," the UN Office for the Coordination of Humanitarian Affairs (OCHA) said.
It is the first time the intensity of American statements and threats has been felt. Even though they have been repeated, this time is considered to be different. We can sense seriousness in dealing with the Syrian file firmly and strongly, in addition to the NATO approval on the Turkish application for deployment of Patriot missiles along its border with Syria. Besides leaving the EU mission with the United Nations to Damascus. Does this mean that there will be air strikes against the regime?
All indicators in Damascus predict that the regime is getting ready for a war. Anyone who enters Damascus through any path will find that the missile bases are fully prepared and this is what pro-regime Al Donia TV mentioned.
It has been more than two weeks and the fighting and shelling are still going in Damascus. The regime looses a lot every day, on the ground, but anyone who knows the Syrian regime knows that it is a stubborn and a dirty one. Therefore it’s too early to expect the end of the Syrian crisis because the regime handles the situation in Syria under the principle of "scorched earth." Moreover, it seems that the regime resumed its dirty crimes, such as killing of students in schools. This means that even if Damascus fell, there is still another place for the regime, which is the Syrian coast.
According to my information, there are some cells relating to the Free Syrian Army in the coastal area. However, these cells cannot activate because the regime, according to opposition sources, sent 120,000 fighters from the Republican Guard and special forces to the coastal areas. It is believed that Assad is living in one of the coastal villages with the Allawites majority.
I hope that there will not be, in the secret plan of great powers, the idea of leaving the Syrian coast to be an Allawite state, so as to execute the plan of dividing Syria into Sunnis and Shiites, as a compromise between the countries that support the regime and the countries that stand against it.