Tourism in Syria has been decimated by more than 17 months of deadly conflict, with hotel rooms once let to foreigners now often occupied by people who are refugees in their own country, official figures show.

Revenue from tourism has plummeted 75.4 percent since the uprising against President Bashar al-Assad's rule erupted, the prime minister's office was quoted as saying by the government daily Tishrin this week.

A government study showed that tourism generated just 12.8 billion Syrian pounds ($178-million at current rates) in the first quarter of 2012, compared with 52 billion in the same period last year - $1-billion at the time.

The tourism ministry said the industry in 2010 accounted for 12 percent of GDP, generating more than $6.5-billion and employing 11 percent of the workforce.

But the anti-regime revolt, which began as a peaceful movement in March 2011 and has steadily militarised in the face of repression, has seen tourist numbers fall by a staggering 76.4 percent and tourism jobs decline by nearly two thirds.

In an effort to halt the slide, Tourism Minister Hala Mohammed al-Nasser only last month suggested that Syrians holiday at home and that expatriates "spend their holidays in their country of origin."

Her comments came amidst ongoing bloodshed which one watchdog says has killed more than 25 000 people. Nasser also stressed the importance of "religious tourism," only weeks before dozens of Iranians were kidnapped by rebels.

Many hotel rooms in Damascus are now occupied not by tourists, but by displaced families fleeing conflict in their home towns or even neighbouring districts of the capital.

The sites that in the past made Syria a favoured tourist destination are themselves also under threat.

According to UNESCO, five of Syria's six World heritage sites have been affected by the fighting: Damascus, Palmyra, the Crac des Chevaliers crusader castle, the ancient northern villages (or Forgotten Cities) and Aleppo, where fighting has raged for more than a month.

The Syrian economy, weakened by nearly a year and a half of revolt, can hold out against international sanctions with the help of "friendly countries" such as Russia, Iraq, Iran and Venezuela, experts believe.

But all indicators are red in the strife-torn country: GDP has collapsed, inflation has skyrocketed, unemployment continues to rise and the current account deficit is widening.