El Siglo Futuro - UK Princess of Wales makes first public appearance since cancer diagnosis

Kate, as she is widely known, has not been seen at a public engagement since a Christmas Day service in December last year, and revealed in March that she was receiving chemotherapy.

The 42-year-old princess said in a statement on Friday she was "making good progress" with her treatment but was "not out of the woods yet".

The future queen added that the treatment is set to last for several more months.

"I'm looking forward to attending the King's Birthday Parade this weekend with my family and hope to join a few public engagements over the summer," Kate said.

The princess was seen arriving by car at Buckingham Palace on Saturday morning with her husband William and her children ahead of the parade.

Kate's announcement that she had cancer came just weeks after it was disclosed that her father-in-law, King Charles III, had also been diagnosed with the condition.

Neither has revealed what type of cancer they have.

British head of state Charles, 75, was given the green light to resume public duties in April, after doctors said they were "very encouraged" by his progress.

His first engagement was meeting staff and patients at a London cancer treatment centre.

Earlier this month, he attended commemoration events in northern France for the 80th anniversary of D-Day.

- 'Our future queen' -

However, unlike previous years when he inspected troops on horseback at Trooping the Colour, Charles will do so this year from a carriage.

His elder son and heir William, 41, will be on horseback.

Spectators on The Mall leading to Buckingham Palace to witness the annual celebration of the king's official birthday welcomed Kate's tentative return to public appearances.

"I was so pleased to hear the news last night," Angela Perry, a teacher in her 50s from Reading in central England, told AFP.

"She's our future queen. She's so important," she added, calling Kate's reemergence "reassuring".

Royal officials will be keen to manage expectations about Kate's gradual return to the public eye, and have maintained that her appearances will depend on her treatment and recovery.

Kate explained in her statement that she had had "good days and bad days" and was "taking each day as it comes".

She is expected to travel with Prince George, aged 10, Princess Charlotte, nine, and six-year-old Prince Louis in a state carriage down The Mall from Buckingham Palace to Horse Guards Parade.

They will watch the parade from a building before returning to the palace for a balcony appearance.

- Protests -

Trooping the Colour marks the British sovereign's official birthday and is a minutely choreographed military tradition dating back more than two centuries.

It starts at Buckingham Palace and moves down The Mall to Horse Guards Parade, where Charles will receive a royal salute before inspecting soldiers.

Charles was actually born in November but the second birthday tradition dates back to King George II in 1748, who wanted to have a celebration in better weather as his own birthday was in October.

The ceremony has its origins in the preparations for war, where all regimental flags -- or colours -- were shown to the soldiers so that they would recognise them in the confusion of battle.

This year's event will include three of five military horses that bolted through the streets of central London in April after being spooked by the noise of building construction.

London's Metropolitan Police said it would mount a "significant" security operation and had been liaising with anti-monarchy group Republic, which kicked off protests at the event.

The force said it had banned "amplified sound" in and around the parade route on public safety grounds and to avoid disruption to the mounted regiments taking part.

Republic's activists, who huddled on a section of The Mall alongside royalists, held aloft placards bearing slogans including "not my king" and "down with the crown".

S.Delgado--ESF