Kate Middleton joins Prince William at ceremonial welcome for Qatar state visit

The state visit is the first for Kate since announcing her cancer diagnosis.

Kate, the Princess of Wales, joined her husband Prince William and his father, King Charles III, in welcoming the leader of Qatar to the United Kingdom Tuesday for a two-day state visit.

Kate and William were the first to greet Qatari Emir Sheikh Tamim bin Hamad al-Thani and his wife Her Highness Sheikha Jawaher bint Hamad bin Suhaim Al Thani, meeting them at their residence Tuesday and then traveling with them to Horse Guards Parade in in St James's Park.

There, the emir and his wife received a ceremonial welcome from Charles, who attended without his wife, Queen Camilla, who is continuing to recover from a chest infection, according to Buckingham Palace.

After the ceremonial welcome, the emir and his wife and Charles, William and Kate traveled in a carriage procession from the Mall to Buckingham Palace for a lunch and tour of a special exhibition of the Royal Collection Trust, according to the palace.

Kate's attendance at Tuesday's events marked another first in her gradual return to public duties, her first state visit since announcing in March that she had been diagnosed with cancer.

Kate has not revealed what type of cancer she was diagnosed with, nor details of her treatment, beyond saying that she underwent "preventative chemotherapy."

The 42-year-old princess shared in a video message in September that she had completed chemotherapy and is now focused on staying "cancer free."

In recent weeks, Kate has traveled with William to Southport, England for an engagement, and joined royal family members at public events marking Remembrance Sunday.

On Friday, Kate is scheduled to host one of her biggest passion projects, her annual Christmas carol service at Westminster Abbey.