Energy-rich Qatar has decided to raise the cost of petrol by a third or more from Friday, according to the state fuel company, amid a slump in global oil prices.

The surprise hike comes into force from midnight (2100 GMT) and has immediately led to queues at some petrol stations in Qatar, according to social media.

The rises were announced by Woqod, the state fuel company, in a memo sent to petrol station managers on Thursday.

Prices for regular petrol will increase to 1.30 Qatari riyals (35 US cents) a litre from 1.00 riyal.

Other products will rise even more steeply, with one, premium petrol, increasing around 35 percent to 1.15 riyals.

Last summer Qatar announced it would face its first budget deficit in 15 years in 2016 because of the fall in energy prices.

In December, it was forecast that lower energy prices would leave Qatar with a hole of around $12 billion in the 2016 budget.