Qatar's budget should be back to "near balance" by 2018, as it overcomes the shock waves from a global fall in energy prices, economists at Qatar National Bank have forecast.

The QNB, in its "Qatar Economic Insight" report, predicts that rising oil prices and the introduction of a value-added tax will help Qatar recover from deficits expected in 2016 and 2017.

"The government's budget balance is expected to register a deficit of 5.3 percent of GDP in 2016 and 2.2 percent in 2017 before recovering to near balance in 2018," the report said.

"The government's revenue is expected to recover in 2017 with rising oil prices. Furthermore, the introduction of a value-added tax (expected to be 5 percent) should boost the government's revenues in 2018 by about 1 percent of GDP."

This year Qatar faces its first budget deficit in 15 years - expected to be more than $12 billion - as the emirate copes with the oil price slump.