RIYADH — Custodian of the Two Holy Mosques King Salman has sent a cable of congratulations to Belgium’s King Philippe on the anniversary of his country"s National Day. In his cable, the Custodian of the Two Holy Mosques wished the Belgian king constant good health and happiness and the government and people of Belgium steady progress and prosperity. Crown Prince Muhammad Bin Salman, deputy premier and minister of defense, sent a similar cable to Belgium’s King Philippe. Belgian National Day is a public holiday and it is celebrated on July 21 each year. In 1830, Belgium gained political independence and regained cultural independence from the United Kingdom of the Netherlands. Up until then, the Belgian area was known as the Southern Netherlands and had been governed by other countries including Spain and France.