Kenya's interior minister has called on US news channel CNN to apologise for calling East Africa a "hotbed of terror" ahead of President Barack Obama's visit on Friday.

It would make an apology "if it was civilised enough", Joseph Nkaissery said at a news conference.

The hashtag #SomeoneTellCNN is trending worldwide as Kenyans condemned CNN, which has not yet commented.

Its report focused on the threat posed by the al-Qaeda-linked al-Shabab group.

Mr Obama was "not just heading to his father's homeland, but to a region that's a hotbed of terror", said the CNN report.

'Soft target'

With its headquarters in neighbouring Somalia, al-Shabab has carried out a spate of attacks in Kenya.

In the worst atrocity, 148 people were killed when it carried out a day-long assault on Garissa University College in April.

Mr Nkaissery said Kenya was at risk of attack like any other country, but this did not turn it into a "hotbed of terror".

"I urge Kenyans to treat the @CNN report with the contempt it deserves," he said, according to a tweet by Kenya's privately owned Daily Nation newspaper.

CNN quoted security analyst Seth Jones analyst as saying that al-Shabab could carry out an attack during Mr Obama's visit.

"Security for the president is likely to be very significant and that means what Al-Shabaab is likely to do, based on what it has done very recently, is go for a soft target," he said.

On Twitter, Kenyans criticised the report.

On Wednesday, Kenya's civil aviation authority said the East African state's airspace would be shut for a 50-minute window ahead of Mr Obama's arrival in the capital Nairobi.

A ban on planes flying lower than 20,000 feet will remain in place in Nairobi for the duration of Mr Obama's three-day visit, it added.

The US issued a travel warning for Kenya in July ahead of the visit.