He suggested that the more than 400,000 British citizens who currently live and work in Spain would no longer have the right to do so if the June 23rd referendum resulted in the UK pulling out of the EU.
"Leaving the European Union would mean that British citizens would lose their right to move freely, work and do business within the largest economic area, the largest market in the world.
Some readers used Twitter to express disbelief that British expats could ever really be kicked out of Spain.
Some even joked that Gibraltar could become a bargaining chip in future negotiations.
While others thought that such scaremongering was political suicide for Rajoy, who, just three days after the EU vote, faces re-election for the second time in six months after the last general election proved inconclusive.
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