File photo of Buckingham Palace, October 14, 2013. President Xi Jinping and first lady Peng Liyuan are to pay a state visit to Britain in October and stay at Buckingham Palace. [Photo/Agencies]

President Xi Jinping is to pay a state visit to Britain in October, the first by a Chinese president in a decade, and stay at Buckingham Palace.

The visit is being viewed as a growing sign of improved relations between the two countries. Xi could be the first head of state to personally congratulate the queen on becoming the longest serving monarch in British history.

On Sept 9, she will surpass the reign of her great, great-grandmother Queen Victoria, who was on the throne for 67 years and 216 days.

The visit by Xi and his wife Peng Liyuan was announced by the queen in her speech on Wednesday outlining the government's legislative program.

Delivering the speech to Parliament, the 89-year-old monarch said she and her husband, Prince Phillip, "look forward to welcoming His Excellency the President of the People's Republic of China and Madame Peng on a state visit in October".

The queen's press secretary said in a statement later that Xi and his wife had accepted the invitation and will stay at Buckingham Palace.

Former president Hu Jintao and his wife stayed at the palace in 2005. No information on the length of Xi's visit has been announced.

Prince William, the queen's grandson and second-in-line to the throne, met Xi in March in the highest-profile visit to China by a member of the British royal family since the queen and her husband paid a state visit to the country in 1986.

On Wednesday, the queen also said her government looked forward to an enhanced partnership with China and India.

Wu Kegang, chief executive officer at trade promotion organization BCC Link to China, said: "It was obviously a very positive speech." It was the first time that China had been mentioned in a Queen's Speech, Wu told Xinhua.

Wu said Xi's visit will create even stronger and more stable links with Britain, adding, "It is also setting the right tone at the right moment for both countries."

A spokesperson of The Confederation of British Industry said: "The United Kingdom's trading partnership with China is of critical importance to our economic future ... President Xi's visit is a timely sign of the ever-deepening importance of that relationship, and will help further strengthen the trading bonds that link our two countries."