An Emirati woman has been sentenced to death by a United Arab Emirates (UAE) court for killing an American kindergarten teacher in December.

The teacher, Romanian-born Ibolya Ryan, a mother of 11-year-old twins, was stabbed to death in a toilet at an Abu Dhabi shopping mall.

The Federal Supreme Court in Abu Dhabi convicted the woman, Ala'a Badr Abdullah al-Hashemi, 30, of the killing and sentenced her to death.

The court's ruling was final and is not subject to appeal.

Hours after killing Ms Ryan, Hashemi had also placed a makeshift bomb outside the front door of an apartment of an Egyptian-American doctor living in the UAE, but the device was safely dismantled.

Police said she had become radicalised over the Internet and had not been targeting an American in particular, but was looking for a foreigner to kill at random.

Attacks on Westerners are rare in the UAE, a wealthy Western-allied oil exporter and tourism hub, but concern has been rising following a spate of attacks in neighbouring Saudi Arabia.

Executions are extremely rare in the UAE and it was not immediately clear when Hashemi might be put to death.