HSBC has corrected what it says as unfounded speculation that its sale of a 16 per cent stake in Ping An Insurance to Thai firm CP Group was in doubt.

The China Insurance Regulatory Commission has requested additional documentation on the planned sale of HSBC's stake, Reuters reports.

In a statement to the news service, the CIRC said it has notified Ping An group to provide additional materials, without providing further details. The deal was first revealed in late 2012, placing the value of the stake at $9.4 billion.

The request spurred media speculation that it may have been triggered by rumours that China Development Bank, a key sponsor of the purchase, is reconsidering its offer to finance the deal.

HSBC, however, corrected what it saw as unfounded speculation, issuing a statement to the media.

"Having made such enquiry with respect to the transaction as is reasonable in the circumstances, HSBC confirms that it is not aware of any information which must be announced to avoid a false market in HSBC’s securities or of any inside information that needs to be disclosed under Part XIVA of the Securities and Futures Ordinance," the statement said.

"HSBC further reaffirms that, on the basis of this enquiry, the information contained in the announcement of 5 December 2012 remains accurate," it added.

Thailand's Charoen Pokphand Group had offered to pay for the 16 per cent stake in Ping An in two tranches. The first is with an outright offering of 20 per cent of the value, while the second would be through funding from the CDB for the rest of the 80 per cent.

The scheduled deadline for the final approval of the transaction is 1 February 2013.