The record marks the currency's highest level since 1994 when China unified its dual exchange rates and set up the Shanghai-based China Foreign Exchange Trade System.

Dealers said on Wednesday there was no sign of intervention by the Central People's Bank of China.

Wednesday's close broke the record set on Tuesday, when the yuan finished at 8.2768.

Analysts say the unusual activity could be a further sign the central bank appears to be testing a wider range for the currency ahead of the country's entry to the World Trade Organisation, which China expects to join this year."Bank traders seemed more inclined to believe a talk of a test after today's trading as the central bank seemed not to intervene for the second day despite the record high closes," said an analyst at Bank of China.

Officials at the central bank declined to comment. Central bank officials told Reuters in February that the government was considering a gradual widening of yuan's trading band as China pursued its bid to join the WTO.Analysts said it was a good time for the central bank to test a wider band as China's economy was showing signs of improvement and exports were surging. China's exports in the first four months of this year rose 39 per cent year-on-year to $72.2 billion, with the country recording a strong trade surplus of $7.3 billion for the period.

"There was a possible test by the central bank to allow the widening of the yuan's trading band judging from trading in the past two days," said a senior foreign exchange analyst with a government institution.