The head of the U.N. mission overseeing the destruction of Syria's chemical weapons arsenal announced Sunday that Syria missed its self-imposed deadline to eradicate its chemical weapons.

While Syria has destroyed more than 92 percent of its arsenal, it missed its deadline to be rid of all weapons by April 27, France 24 reported.

However, Sigrid Kaag, the head of the UN mission overseeing the destruction of Syria's chemical weapons, said she is still hopeful that the country can meet a June 30 deadline.

"We also however need to ... ensure the remaining 7.5-8.0 percent of the chemical weapons material is also removed and destroyed," she said, adding that the remaining armaments are located at "one particular site."

"However, 92.5 percent of chemical weapons material removed or destroyed is significant progress," she said.

Syria signed on to the Chemical Weapons Convention last year under a U.S.-Russian deal in which they agreed to destroy their entire chemical weapon arsenal by June 30, 2014.

Despite security challenges in the country, Kaag said Syria is required to meet its commitment.

"Success is around the corner, and this last push is very much needed," she said. "The June 30 deadline is around the corner. ... And we are hopeful that this is possible and will be met."

Yet, Syria has missed previous deadlines, and there is a current dispute over whether Syria will need to eradicate its 12 remaining sites for chemical weapons production. Damascus wants to seal the sites, which have been rendered unusable, but the West wants them destroyed.

Developments have also been marred in recent weeks over questions about alleged chlorine gas attacks, which the government blames on a jihadist group. However, activists say they were carried out by government forces.

Adding to the turmoil, Syrian President Bashar al-Assad declared Monday that he will run for re-election in a vote on June 3, according to NDTV.

The election is expected to secure Assad a third term, despite a three-year civil war that begun out of protests to his dictatorial regime.

Parliament Speaker Mohammad al-Laham made the announcement in a televised session of Syria's parliament.

Both Western and Arab powers have condemned the election, saying it cannot be a credible election in the country, considering 6 million people have been displaced, 2.5 million have fled and hundreds are killed on a daily basis.

Violence has not ceased between government officials and rebels. In the past few weeks, the Syrian Observatory for Human Rights said a mortar attack by rebels on government-held parts of Aleppo killed at least 21 people.

It also reported that extreme air raids with barrel bombs killed at least six people in neighborhoods in the east of the city.