Image copyright Reuters Image caption Mr Tsang was chief executive of Hong Kong from 2005 to 2012

The former leader of Hong Kong, Donald Tsang, has gone on trial for corruption.

Mr Tsang pleaded not guilty to three charges of bribery and misconduct, relating to a luxury flat in China.

He is the highest-ranking retired official to be tried for corruption in Hong Kong and faces possible jail time in a case that has worried a city known for its clean reputation.

Mr Tsang served as chief executive of Hong Kong from 2005 to 2012.

He faces charges of misconduct and accepting advantages as chief executive over events which took place near the end of his term, between 2010 and 2012.

'Bowtie Tsang' in the dock - Helier Cheung, BBC News, Hong Kong

Mr Tsang looked solemn as he stood in the dock, and pleaded "not guilty" to all three charges.

The former leader was popular when he first took office - he was considered competent, and more charismatic than his predecessor Tung Chee-hwa.

He had worked as a civil servant under British rule and was even awarded a knighthood in 1997 for his services to Hong Kong. People affectionately nicknamed him "Bowtie Tsang", after the accessory he liked to wear.

But by the time his term ended, his reputation was badly damaged by corruption allegations.

Hong Kong prides itself on its clean reputation - but this case has raised questions over the relationship between tycoons and government officials.

Prosecutors allege Mr Tsang engaged in a number of conflicts of interest without declaring them, including renting a luxury flat in southern China from the shareholder of a broadcast company, Wave Media, whose license applications he approved.

They allege the flat was redecorated for free for him and that he later nominated the interior designer for an honour.

Mr Tsang, 72, has previously insisted his conscience is clear.

Image copyright AFP Image caption Prosecutors also claim Mr Tsang approved a chairmanship appointment at Wave Media without declaring a conflict of interest

He first came to power promising a "clean and efficient" civil service, according to the South China Morning Post.

But his term ended in scandal when the penthouse claims came to light, launching a three-year inquiry culminating in the trial.

His deputy was also jailed for bribery two years ago.