In a televised, 7-minute address to the nation, the King, 79, said "my age and my health do not allow me to practice as I would like."
He mentioned he will make another address July 20, the last in his 20-year reign, and will attend the ceremony transferring power the following day, a national holiday.
He told the country's ministers of his plans earlier Wednesday, the news website FlandersNews.be reported.
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