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After being criticized for not doing enough to help refugees, Saudi Arabia's Ministry of Foreign Affairs declared that they have been helping after all. Among others, it specifically claims that it has taken more than 2.5 million Syrians.
The Kingdom has received around 2.5 million Syrians since the beginning of the conflict. In order to ensure their dignity and safety, the Kingdom adopted a policy that does not treat them as refugees or place them in refugee camps. They have been given the freedom to move about the country and those who wish to remain in Saudi Arabia (some hundreds of thousands) have been given legal residency status like the remaining residents. Their residency comes with the rights to receive free medical care, to join the labor market and to attend schools and universities. This was contained in a royal decree in 2012 that instructed public schools to accept Syrian students. According to government statistics, the public school system has accepted more than 100,000 Syrian students.
This is surprising, not because I doubt the Saudis' generosity, but because the sheer number. 2.5 million would surpass what any other country hosts. This data sheet shows Turkey host 1.9 million, and is thought to be the country with the most Syrian refugees. Note that Turkey is closer to Syria and more populous than Saudi Arabia ( you could even say richer if you count total GDP). The data sheet also shows that in total, all the (non-Saudi) countries are thought to host about 4 million, so 2.5 million is more than half that.
Are there other data or information that corroborate or give serious doubt to this very specific claim?