(JTA) — Syria has scattered its stockpile of chemical weapons in a bid to complicate U.S. efforts to track them, the Wall Street Journal reported.

A secretive Syrian military unit had been given responsibility to shift the arsenal of poison gases and munitions, the newspaper reported Thursday, raising questions about the viability of a Russian plan to secure the weapons.

Unnamed American and “Middle Eastern” officials told the paper moving the stockpiles could complicate a possible U.S. military strike on Syria over the Damascus regime’s alleged use of chemical weapons.

Washington alleges that about 1,400 people died in an August 21 attack involving poison gas.

President Barack Obama has agreed to hold off on plans to strike the forces of Syrian President Bashar Assad over their alleged use of chemical weapons, pending the implementation of a Russian plan designed to avert the attack. The plan calls for placing Assad’s suspected chemical weapons arsenal under international control and inspection.

The weapons, which used to be concentrated int he country’s west, have been deposited by Syria’s unit 450 in over 50 sites in Syria’s north, west and south, according to what officials told the Journal.

Despite the redistribution, both US and Israeli intelligence agencies still believe they know where most of the weapons are situated, according to the Journal.

Obama has said that his military chiefs have assured him that any U.S. strike would not be degraded by delays.

Assad said Thursday Israel should be required to get rid of its weapons of mass destruction, including chemical weapons, before Syria does so, but his country applied that day to join the United Nation’s Chemical Weapons Convention – a move interpreted as showing compliance with demands Syria relinquish its arsenal.

Obama on Tuesday warned the Syrian government that Israel can defend itself with “overwhelming force” if attacked by Syria. Russian President Vladimir Putin, meanwhile, warned in a New York Times op-ed published Thursday that the Syrian rebels fighting to topple the Assad regime are preparing to strike Israel.

“Reports that militants are preparing another attack — this time against Israel — cannot be ignored,” he wrote.