London  - Prince William flew a transport plane on a secret visit to British troops in Afghanistan, royal officials said late Tuesday.

The 25-year-old, second in line for the British throne behind his father, flew a C-17 Globemaster military transport plane to Kandahar where he spent three hours meeting with troops on Monday, according to a spokesman for Clarence House, the official residence of William's father, Prince Charles.

The 30-hour trip was conducted in secret for security reasons.

The purpose of the trip was for William, a trained pilot, to familiarise himself with Royal Air Force (RAF) operations in a battle situation, according to the royal official, who described the mission as a "success."

His grandmother, Queen Elizabeth II, and father, the Prince of Wales, gave their consent to the trip, Clarence House said.

Prince Charles was also an RAF pilot, completing his flying training course in 1971.

William's visit to Afghanistan follows that of his brother Prince Harry, 23, who served in Helmand province for 10 weeks. Harry's tour was cut short after the media reported his presence on combat duty in the southern province.

There are some 8,000 British soldiers stationed in Afghanistan for the US-led fight against Taliban insurgents. (dpa)