Qatar's stock market tumbled more than 7 percent on Monday as six of the Middle Eastern country's neighbors reportedly severed diplomatic relations with Doha for allegedly supporting terrorism.
The key stock index in Doha slipped shortly after Monday's open – the benchmark's sharpest fall in more than seven years – before paring some its losses to trade down 7.2 percent at around 3:00 p.m. local time.
Six countries, including Saudi Arabia and Egypt, had all coordinated on Monday to accuse the wealthy Gulf state of supporting terrorism, which Qatar has denied. Investors viewed the diplomatic withdrawal as a major breakdown between powerful Gulf nations, who are also close U.S. allies.
While Saudi Arabia – the world's leading crude oil exporter – said Qatar had supported "Iranian-backed terrorist groups," Qatar described the joint decision as having "no basis in fact" and was therefore "unjustified".
Political tensions in the region had been building in recent weeks as Egypt, Saudi Arabia, Bahrain and the United Arab Emirates – all countries to have cut relations with Doha on Monday – had blocked Qatari-based news sites in May.
However, Monday's decision was reported to be based on Qatar's alleged role in supporting Islamist groups and its stance concerning Iran – a regional rival to Saudi Arabia.
Qatar, a member of the U.S. coalition against the so-called Islamic State, has frequently and consistently rejected accusations from Iraq's Shia leaders that it has provided financial backing to ISIS.
"Whilst Qatar is the member of the U.S. coalition against IS, wealthy individuals have reportedly made donations to extremist groups and the government is also accused of supporting extremists - allegations that Qatar vehemently deny," Tamas Varga, oil associates analyst at PVM, said in an email on Monday.
U.S. President Donald Trump visited Saudi Arabia's capital city of Riyadh two weeks ago and called on Muslim nations to take the lead in resolving radicalization. Trump also singled out Iran for creating instability in the region.
"It seems that the Saudis and Emiratis feel emboldened by the alignment of their regional interests - toward Iran and Islamism - with the Trump administration," Gulf analyst Kristian Ulrichsen told Reuters on Monday.
As a result of the move and the subsequent dramatic sell-off from investors, Qatar's main equity benchmark became the worst global performer this year. While shares from emerging markets have soared more than 18 percent in 2017, Qatar has recorded losses of approximately 12 percent over the same period.
Oil prices reversed all of its gains on Monday to trade lower amid fears that the multiple Gulf States cutting ties with Qatar could hamper a global deal to curtail a global supply overhang.
"Given the persisting bearish sentiment in the oil market the unprecedented move might not have a long-lasting impact on oil prices but it is worth keeping in mind that Persian Gulf countries produce about 21.5 million barrels per day," PVM's Varga added.