Oman's ageing Sultan Qaboos to travel to Belgium for medical checks

Sultan Qaboos bin Said left "for some medical checks that will take a limited period, God willing", the Oman News Agency reported on Saturday, citing a royal court statement.

He is believed to be suffering from colon cancer and has taken multiple medical trips abroad in the past, rarely appearing in public since as a lengthy hospital spell in Germany in 2015.

The British-educated sultan rose to power in 1970, overthrowing his father in a bloodless coup.

Repeated reports of Qaboos' ill health have increased attention on the fact he has no designated successor.

The sultan is unmarried and has no children or brothers.

According to the sultanate's constitution, Qaboos should designate a successor in a sealed envelope to be opened if his family cannot agree on a replacement within three days of his death.

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