BRUSSELS - Belgium will swear in a new king on Sunday with festivities but also questions over the political influence of the monarch and the acceptance of Philippe as the king of all Belgians.

The 183-year-old country is split across the middle, with many Dutch speakers seeking greater independence for Flanders in the north and wary of a monarchy seen rooted in the once powerful, but now poorer French-speaking Wallonia in the south.

"One king, two nations" was a headline in French language business daily L'Echo, while Dutch newspaper De Standaard pushed the royals deep inside its weekend issue, leading instead with a story on tax.

Fewer than half of people in Flanders believe Philippe will be a good king after 79-year-old King Albert II steps aside, against two-thirds in Wallonia, according to a poll.

Business leaders are similarly divided, with French speakers content with the status quo, but Dutch-speaking counterparts saying the monarch no longer have a political role.

Belgian kings - and 53-year-old Philippe will be the seventh - do plenty of handshaking and ribbon-cutting, but also appoint mediators and potential government heads to steer coalition talks after elections, no small task in Belgium.

After the inconclusive 2010 vote, Albert held countless meetings with Belgian politicians as they failed for a world record 541 days to form a new government.

The Flemish separatist N-VA, the largest party in parliament but eventually dropped from coalition talks, has been particularly vocal about limiting royal powers.

Neighbouring Netherlands did just that last year. Queen Beatrix also stepped aside to allow her popular son Willem-Alexander to become king amid wild celebrations.

Philippe's investiture comes just two-and-a-half weeks after the king, at 79, said it was time to make way. The ceremony has been tagged on to festivities already planned for July 21, which is Belgium's national day and also marks 20 years of Albert's reign.

The Belgian government, mindful of the savings it has forced on the public, has said this should help cap costs.    

In a last address to the nation on Saturday, Albert listed his wishes for the future, including that Belgium stay united and that the country of 11 million people back his son as king.

"Give the future King Philippe and the future Queen Mathilde your active participation and your support. They make a great couple serving our country and they enjoy my full confidence," he said in a broadcast sitting in front of a portrait of Leopold I, Belgium's first king, and concluding with Albert beside his son on a bench in the palace's grounds.

Even royalist Belgians probably know feel they know little about Philippe, who has appeared reserved in public, in contrast to his more outgoing father.

The Oxford and Stanford-educated prince, who has also trained as a Belgian air force pilot and led trade missions, knew from an early age he would become king.

However, when his childless uncle Baudouin died of a heart attack in 1993, Philippe at 33 was considered too young to succeed so his father ascended to the throne.

His key trump card is wife Mathilde, who will be the first Belgian queen actually born in Belgium and whose natural style and charity work has made her popular across the nation.