The group said in an article in its English-language online magazine Dabiq that the weapon could be smuggled into the United States via its southern border with Mexico.
British journalist John Cantlie wrote in the article ISIL has billions of dollars in the bank, so they call on their wilayah (Province) in Pakistan to purchase a nuclear device through weapons dealers with links to corrupt officials in the region.
The weapon is then transported overland until it makes it to Libya, where the mujahidin move it south to Nigeria, the journalist said.
He added that drug shipments from Columbia bound for Europe pass through West Africa, so moving other types of contraband from East to West is just as possible.
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John Cantlie[/caption]Cantlie continued the weapon and accompanying radicals would then move up through Central America and Mexico before entering the US.
"From there it's a quick hop through a smuggling tunnel and hey presto, they're mingling with another 12 million 'illegal' aliens in America with a nuclear bomb in the trunk," he wrote.
"Perhaps such a scenario is far-fetched but it's the sum of all fears for Western intelligence agencies and it's infinitely more possible today than it was just one year ago, Cantlie said.
Cantlie is a photojournalist who was abducted in Syria by ISIL in November 2012. He has appeared in several videos since his abduction and criticized Western powers.
The journalist also said President Barack Obama's policies against ISIL have failed.
The report comes while the terror network has gained grounds in Iraq and Syria.
The terrorists took control of the major Iraqi city of Ramadi and the Syrian ancient city of Palmyra.
The ISIL terrorists, who were initially trained by the CIA in Jordan in 2012 to destabilize the Syrian government, are engaged in crimes against humanity in the areas under their control.
They have been carrying out horrific acts of violence such as public decapitations and crucifixions against all communities, including Shias, Sunnis, Kurds, and Christians.
By Press TV
