Despite last year’s agreement to rid Syria of its chemical weapons, the program has reportedly come to a stop over a debate about what to do with the facilities that stored the weapons. According to The Washington Post, eight percent of the country’s chemical weapons arsenal remains in the country. That includes 27 tons of sarin precursor.

The stalemate concerns the tunnels and buildings that previously stored the weapons. The Organization for the Prohibition of Chemical Weapons insists that the facilities to be destroyed. Officials in Assad’s regime are arguing that the facilities would be put to better use repurposed.

One U.S. official told the post that they perceived Syria’s insistence on repurposing the facilities to be a stalling tactic.

Meanwhile, Syria is under investigation elsewhere for using chlorine in barrel bombs. Doing so would be a violation of the Chemical Weapons Convention the country signed last August. Soil samples from the attack areas registered high levels of chlorine.

Chlorine poses a trickier obstacle than sarin gas, since the chemical has a number of legitimate uses that make it difficult to justify getting rid of completely.

A separate inquiry is also underway to investigate discrepancies between Syria’s declared quantities of chemical weapons and the amount already shipped out.