Twenty people from across Oxfordshire swore an oath of allegiance to the Queen today - overseen by her daughter.

The Princess Royal was in the county for a series of engagements and her first stop was County Hall in New Road, Oxford, to meet those taking part in the ceremony.

Those applying for citizenship came from countries around the globe, including the Philippines, Malaysia, Zimbabwe, the Sudan, Nigeria and Iran.

Following her arrival, Princess Anne was given a posy of flowers by nine-year-old Trisha Gelig, from Cowley.

Trisha was attending the ceremony with her father Tyrovani, 39, mother Maria, 35, and sister Alyssa, one.

Mr Gelig, who works for a scientific instruments company in Eynsham, said: "I was delighted to meet Princess Anne and become a British citizen.

"I arrived from the Philippines in 2001 and we were granted permanent residence in the UK two years ago.

"Sometimes I go back to the Philippines for a holiday and when I am there I miss the fish and chip shop in Headington.

"The weather is much colder over here but it's a much more progressive country and I have better career opportunties."

Alvin Doxon, 27, came to the UK from St Lucia in 2002 when he joined the Royal Logistics Corps at Dalton Barracks in Abingdon.

He has since served on a peacekeeping mission in Basra and told the Oxford Mail: "What I like about Britain is the tolerance for so many different kinds of people."

Foreign nationals can apply to become British citizens after living in the country for five years. The citizenship ceremony became compulsory in 2004.

The county's Superintendent Registrar Alicjacrct Gilroy said: "The Princess Royal's visit makes this an extra special day for our citizens."

Citizenship ceremonies, which last 30 minutes, take place in Oxford every week, and more than 1,000 foreign nationals in the county obtain British citizenship each year.

It was the Princess Royal's first visit to a citizenship ceremony in the county.

Oxfordshire's Lord Lieutenant Hugo Brunner, who invited the Princess to attend, said: "It was a great honour for us."

After the County Hall visit, Princess Anne went to the Warneford Hospital in Headington to officially open the new £2.3m Oxford Neurodevelopmental Magnetoencephalography (MEG) Centre, at Oxford University's Department of Psychiatry.

Scientists are using the first purpose-built brain scanner to study the brain activity of autistic children and adults while they complete tasks, with the aim of gaining a better understanding of the condition and finding better treatments.

The Princess Royal spoke to staff and people with autism and associated disorders.

The MEG machine measures the tiny magnetic fields generated by brain activity, allowing scientists to pinpoint what parts of the brain are working when a patient completes a task.