In their toughest fight for survival, two pairs of Russian Amur Tigers will have to change citizenship. The animals will soon be sent to Iran to help local zoologists repopulate the country with the world's biggest cats.

­Iran’s Caspian tiger population has been all but wiped out by hunters, so local preservation specialists chose the Amur tiger as a replacement as it is genetically close to the domestic big cat.

There are only a few hundred Amur tigers left in Russia. According to international law, the purchase and sale of rare animals is forbidden, but gifts are welcome.   

The Amur tigers will have their new home at Iran's Miankaleh wildlife reserve on the Caspian Sea coast, where they are scheduled to arrive later this year.

It’s not the first time Siberian tigers are being sent to Iran. In 2010, two tigers from Russia were housed at a zoo in Tehran for a multimillion breeding program to repopulate northern Iran with the animals.
One of the pair died soon after arriving in Iran however, having developed a deadly respiratory infection. Some local officials said the tiger was already sick when it arrived, but Russian officials and members of the World Wildlife Foundation strongly rejected the claim.

Russia has heavily invested in preserving its tiger population, with Prime Minister Putin famously endorsing an international protection campaigns alongside Hollywood celebrities like Leonardo DiCaprio.

The Russian Far East is the world’s biggest tiger habitat, accounting for about 11 per cent of the planet’s tiger population. However, poachers and a loss of habitat continue to drive Amur tigers towards extinction.