Members of the Royal Family and politicians are due to greet China’s President Xi Jinping at the start of his four-day state visit to the UK.
Mr Xi and his wife, Peng Liyuan, will take part in a procession along The Mall to Buckingham Palace, ahead of a state banquet held by the Queen later.
Foreign Secretary Philip Hammond said Britain was going into closer relations with China with its “eyes wide open”.
He denied allegations the UK was acting like “a panting puppy” towards Beijing.
Ministers expect more than £30bn of trade and investment deals to be struck during the four-day visit, which will also include talks between Mr Xi and Prime Minister David Cameron.
A Downing Street spokeswoman said “nothing is off the table” in the talks.
But Mr Hammond denied the government was being “naive”, saying it was “very much in our national interest to engage with China”.
“I think we are developing a mature relationship with the Chinese,” he said.
“They know that we are looking not just to China but to many other countries for infrastructure investment in the UK.”
The trip – the first UK state visit by a Chinese leader since 2005 – has been hailed by officials from both countries as the start of a “golden era” of relations.
The Treasury hopes to establish China as Britain’s second biggest trading partner within 10 years.
Chinese companies are to be allowed to take a stake in British nuclear power plants, and a trip by Mr Xi and Mr Cameron to Manchester later in the week is expected to see the announcement of further investment in the so-called “Northern powerhouse” project.
But the visit comes as China’s economy grew by just 6.9% in the third quarter, the weakest rate since the global financial crisis.
China and the UK
The president will begin his visit on Tuesday by being greeted by the Prince of Wales and Duchess of Cornwall at the Royal Mandarin Hotel in London.
He will then inspect a guard of honour at Horse Guards Parade, where he and his wife will also be given a ceremonial welcome by the Queen and Duke Of Edinburgh.
A state carriage procession will then take them to Buckingham Palace.
Mr Xi will later travel to Westminster where he will address MPs and Lords at the Palace of Westminster.
He will then visit Clarence House for a further engagement with Prince Charles and the Duchess of Cornwall, before arriving back at Buckingham Palace for meetings with the Duke of Cambridge and, afterwards, Labour leader Jeremy Corbyn.
The Queen will round off the day by hosting a state banquet in the president’s honour, which will be attended by members of the Royal Family – including Prince William and the Duchess of Cambridge – as well as Mr Cameron and Mr Corbyn.
Prince Charles, will not be attending, but no official reason has been given for his absence.