The United States says it has indications that toxic chemicals were released in a rebel area in Syria this month.
U.S. State Department spokeswoman, Jen Psaki said Monday that the United States is looking into allegations that the Syrian government was responsible. She said there is evidence an industrial toxic chemical, likely chlorine, was used in the town of Kfar Zeita.
On Sunday, French President François Hollande said France also had indications that chemical weapons are still being used in Syria.
President Bashar al-Assad's government agreed last year to destroy its chemical weapons, as part of a deal to de-escalate tensions following mounting international pressure.
Washington and its allies say Assad's forces unleashed sarin gas last year, causing the deaths of hundreds of people.
The Syrian government blamed the rebels in Syria's civil war, which is now in its fourth year.
In another development Monday, Syria's government announced that presidential elections will be held June 3, giving President Assad the chance to win a third seven-year term in office.
The opposition immediately dismissed the election as a farce.
Assad has been in power since 2000 when he took office following the death of his father, who had ruled Syria for 30 years.
The president won his second term in 2007, taking 97 percent of the vote in an election boycotted by the opposition and one in which he was the only candidate on the ballot.
Assad has been battling rebels in a conflict that began as peaceful protests in March 2011 and quickly grew into a civil war that has killed more than 150,000 people.
Another 2.6 million people have fled Syria to surrounding countries, and the crisis has displaced more than 6.5 million people within Syria.