HONG KONG (Reuters) -CK Hutchison said on Monday it wants a major Chinese strategic investor to join the consortium bidding for its $22.8 billion ports business, after media reports that state-owned China COSCO Shipping Corp may join the group.

In a statement, CK Hutchison said changes to the consortium's composition and the structure of the transaction will be necessary for the deal to secure regulatory approvals, and that it will allow as much time as needed to achieve those.

The announcement comes as a 145-day exclusivity period for talks between CK Hutchison and the original bidding consortium - led by BlackRock and Gianluigi Aponte's MSC - expired on Sunday.

The deal, which includes two ports near the strategically crucial Panama Canal, has become highly politicised as tension escalates between China and the United States.

Beijing views the potential sale as a threat to its interests, seeing the BlackRock-led consortium as a proxy for growing American influence in a region China considers economically and geopolitically significant.

The outlook for the deal has grown increasingly uncertain in recent days, with sources telling Reuters that COSCO - a key player in China's global maritime ambitions - is exploring a role in the bid.