Prince William and his aunt Princess Anne have today joined royals from around the world at the funeral of King Harald V of Norway.

The Prince of Wales represented his father, King Charles, at the service at Oslo Cathedral, while the Princess Royal attended in a private and personal capacity as godmother of the new king, Haakon VIII.

They were joined by other European senior royals including King Felipe of Spain and Princess Charlene of Monaco. 

The coffin was taken from the royal palace to the cathedral in a procession of senior Norwegian royals including King Haakon, foreign guests and representatives from Norway’s and other parliaments. 

Haakon walked behind the coffin, draped with the red Norwegian royal standard, alongside his oldest child, Crown Princess Ingrid Alexandra, now heir to the throne, his son Prince Sverre Magnus and his sister Princess Martha Louise.

The King's stepson Marius Borg Hoiby, 29, who is currently serving a four-year prison sentence under house arrest at his parents' Skaugum Estate while he appeals his conviction for two counts of rape, also joined members of the Norwegian royal family at the cathedral.

He previously joined his relatives to carry the coffin of Harald from the Royal Palace to the palace chapel last week while temporarily released, sparking fierce backlash from royal fans, many of whom strongly condemned his presence at the occasion. 

His mother, Queen Mette-Marit, who missed her husband's swearing-in ceremony due to 'complications' from her recent lung transplant surgery in June, and Harald's widow, Queen Sonja, followed the coffin in a car. 

King Frederik and Queen Mary of Denmark and King Carl XVI Gustaf and Queen Silvia of Sweden also joined the procession.

Thousands of people lined the streets of the Norwegian capital to bid a final farewell to Harald, who reigned for 35 years.

Political leaders including Norwegian prime minister Jonas Gahr Store and Ukrainian President Volodymyr Zelenskyy were also in attendance. 

People were tuning in from across the country. Scores of churches, libraries, cultural centers and city halls were making big screens available for the public to watch the funeral, public broadcaster NRK reported.

A 21-gun salute rang out over the capital at the start of the funeral procession from the royal palace to Oslo Cathedral.

King Charles paid tribute to his 'dear cousin' and 'much-loved kinsman and friend' after news of Harald´s death was announced.

In a statement released by Buckingham Palace, he said the monarch served the people of Norway with 'unwavering dedication' and guided them through times of change with 'warmth and humility'.

Under royal precedent, the sovereign does not attend funerals of other heads of state, and so the duty fell to William. The Prince of Wales represented his father at the funeral of Pope Francis in the Vatican in April last year.

William and the now-Princess of Wales carried out an official tour to Norway in 2018.

On September 8, a group including Felipe and Queen Letizia of Spain, the former Grand Duke of Luxembourg Henri, Crown Prince Alexander of Yugoslavia and Crown Princess Katherine of Serbia, Prince Alois of Liechtenstein, Princess Alexia of the Netherlands and Queen Anne-Marie of Greece travelled together by transit bus to the Palace for the ceremony.

Passing away on 28 August aged 89, King Harald V was Europe's oldest reigning sovereign, ruling over Norway for 35 years.

Yet, despite modernising his family's rule over the years, he refused to step down like other ageing monarchs.

His son immediately became King Haakon VIII and last week pledged an oath of allegiance to Norway's constitution in parliament.

In attendance are The Netherlands' King Willem-Alexander, Queen Maxima, Princess Beatrix and Princess Catherina-Amalia, along with Prince William, Princess Anne, Denmark's King Frederik, Queen Mary, Crown Prince Christian and Princess Benedikte.

Other royal guests include Sweden's King Carl XVI Gustaf, Queen Silvia, Crown Princess Victoria, Prince Carl Philip, Princess Sofia, Princess Madeleine and Princess Christina.

Ahead of the funeral, Norwegians waited patiently to file past Harald's coffin as it lay in state in the chapel of the royal palace in Oslo, with the queue stretching seven hours long over the weekend.

After the funeral, Harald's coffin will be taken in a procession to the palace chapel at Akershus Castle, where the late king's ancestors are buried.

After a private ceremony for the Norwegian royals, who will be joined by some of the foreign guests and senior Norwegian officials, it will be lowered into the crypt.

The Norwegian royal house has kinfolk in other European royal families. Harald and Haakon are related to both King Charles and Spain's King Felipe. They´re all descendants of Queen Victoria.

Today, the throne's role in Norway is largely symbolic and power lies with the elected government and parliament, but the Norwegian royal family retains a role in promoting the wealthy Scandinavian nation around the world.

Norway´s monarchy traces its origins to King Harald Fairhair in the ninth century. When Norway regained its independence from Sweden in 1905, three-quarters of voters in a national plebiscite approved restoring the monarchy.

A minute's silence will be held across Norway at the start of the funeral ceremony. Eulogies will be delivered by Norway's parliament speaker and prime minister, and there will be a candle-lighting ceremony with representatives of different faiths.

The government says it's not an official holiday, but schools and workplaces could individually opt to let students and employees tune in for today's events. The government advised that 'noisy events should be suspended while the funeral is ongoing'.