There could be major disruptions for Australians with travel plans to the Middle East or over the top into Europe.
It started overnight with a move by Saudi Arabia, Egypt, the United Arab Emirates and Bahrain to sever ties with Qatar. They've accused the tiny country of supporting terrorism.
So what does it mean for us?
Saudi Arabia has banned Qatari airlines from flying across it's massive airspace, while Abu Dhabi's state-owned Etihad Airways and Dubai's Emirates Airline said they would suspend all flights to and from Doha.
Qatar is also the home to global airline Qatar Airways, which has services direct into Perth, Adelaide, Melbourne and Sydney.
"There is a wider impact than Qatar Airways not being able to land in markets like Saudi and UAE since those markets are significant sources for transfer traffic," said Will Horton, a senior analyst at CAPA Centre for Aviation in Melbourne.
"A Riyadh passenger may not be able to connect to Bangkok via Doha and a Dubai passenger could not get to London via Doha."
Interestingly, the United States doesn't see the situation the same was as Saudi Arabia, Egypt, the United Arab Emirates and Bahrain. Yesterday the US lauded Qatar for its "enduring commitment to regional security".