DUBAI - Oman's Sultan Qaboos, who left home for medical tests six months ago for suspected cancer and hasn't returned since, has stirred concerns over stability in his small Gulf country and his eventual succession.
The 74-year-old absolute ruler is not only sultan, but also prime minister, as well as holding the foreign affairs, finance, defence and interior portfolios.
But without children, or even brothers, his closest relatives being cousins, he has no direct heir.
Qaboos, who has been on the throne for 44 years, went to Germany in July for medical tests, with one diplomat saying he suffers from colon cancer.
Since then, he has made only one appearance, in a brief video that was broadcast on national television on Nov 5.
In it, a visibly weakened Qaboos spoke of what he called the "good results" of his treatment, but added that his condition requires monitoring.
Speaking to AFP in Muscat, a Western diplomat said that, "by way of this undated video, the sultan wanted to show that he remains in control of the country, even continuing to issue decrees from his place of residence abroad." When he took the reins of power, Oman was an isolated country living on the margins of the modern world with little or no infrastructure.
Qaboos has since transformed the sultanate into a modern state.
In 2011, Qaboos amended the process for choosing his successor. He appointed five top officials to a council that would be involved in confirming the new sultan in case of any royal family dispute.
"But as he has not assigned prerogatives, nobody can make decisions in his place" during his life, another diplomat said.
The diplomat said that posed problems amid an economic slowdown that is likely to worsen after the price of crude has nearly halved since June.
The sultanate derives 79 per cent of its revenues from oil, of which it produces only about one million barrels per day.
The non-OPEC member has announced this year a budget deficit of US$6.47 billion (S$8.65 billion), representing 8.0 per cent of GDP.
Current expenditure accounts for the lion's share at 68 per cent of public spending, far ahead of investments (23 per cent).
Risks of instability
"Despite their reassurances that minimise the impact of falling oil revenues, Omani officials fear a slowdown in investments and therefore, the suspension of major infrastructure projects," the first diplomat told AFP.
In 2008, Oman announced plans to build a port and shipyard in Duqm, designed to handle ultra-large crude carriers and compete with Dubai's Jebel Ali free zone. But the project has never moved beyond its first phase.
Aware of the consequences of the government's fiscal problems, officials have been struggling to diversify revenues beyond oil.
A proposal to impose a two per cent tax on foreign workers' money transfers to their home countries, which amounted to an officially estimated US$7.2 billion in 2013, was abandoned following extensive debate.
Oman's population is estimated at around four million. Nearly 1.8 million of them are foreigners - mostly Asians.
In 2011, the usually sleepy sultanate was caught up in the Arab Spring protest movement that touched much of the region.
Two civilians died in demonstrations demanding political and economic reforms, shaking the government and leading Qaboos to implement a series of reforms and to arrest scores of activists.
In an effort to placate protesters, Qaboos announced the creation of 50,000 new jobs, a monthly allowance for registered job seekers and a higher minimum wage for nationals working in the private sector.
But the genie could again escape from the bottle.
Increased financial pressures, coupled with uncertainty surrounding Qaboos's health and the speculation over his successor, have fuelled fears of further unrest, according to residents in Muscat.
"This time, violence could erupt again in the industrial area of Sohar (in the north), which saw the most violent protests in 2011 and where residents complain about the poor distribution of national wealth," warned the diplomat.