Syrian President Bashar al-Assad issued a decree Sunday banning the use of foreign currency in commercial transactions, state news agency SANA said.
"It is prohibited to make payments, reimbursements, commercial transactions and any other commercial operation in foreign currency or in precious stones," SANA quoted the decree as saying.
"The Syrian lira is the only currency" allowed in business and commerce, it added.
Those breaking the law risk jail sentences from between six months to 10 years of hard labour, depending on the sum involved, and will be fined.
The US dollar is the preferred foreign currency in Syria where the lira has lost three quarters of its value against the greenback since the outbreak of the anti-regime uprising more than two years ago.
At the start of the conflict in March 2011 one dollar fetched 50 liras. while a dollar today is worth more than 200 liras.
Dollars have been used in the sale of land, namely in the upscale Damascus suburbs, and by importers who trade in goods such as rice, sugar, textile and electronic equipment.