Twenty years ago this Sunday, Britain signed the historic Joint Declaration to return Hong Kong to China. Back then, at the height of the cold war, the 'one country, two systems' principle at the heart of the agreement was seen as a daring political experiment. One of the world's freest economies was to be run by a communist state, albeit one that had started to reform.
As foreign secretary from 1983, Geoffrey Howe, now Lord Howe of Aberavon, led the British side on the often difficult path towards the deal. Negotiations began after China made clear that it wanted to resume control over Hong Kong in 1997 after the expiry of the 99-year lease that allowed Britain to hold the New Territories. Britain quickly realised that holding on to Hong Kong island and Kowloon - which account for only 8 per cent of the territory - was not a viable option.
'We had to find a way of ensuring continuity of administration after having conceded that we couldn't secure continued British administration,' said Lord Howe in an interview with the South China Morning Post at the House of Lords. During the negotiations, Lord Howe likened the transfer of sovereignty to a relay race with a Ming vase that had to be carefully handed over.
China was keen to preserve Hong Kong's prosperity after 1997, which led Deng Xiaoping to coin the phrase 'one country, two systems' - a model that Deng hoped would also work elsewhere.
'He used it to refer to other places. He thought it was a solution for East Germany/West Germany, North Korea and South Korea,' said Lord Howe. 'It hasn't quite worked out in either of those other places, but it has worked out in respect of Hong Kong.'
Given China's limited experience with market economies at that time, Lord Howe believes the Joint Declaration was essential to maintain investor confidence - a concept that in those early days of the mainland's market reforms wasn't well understood.