HONG KONG (Reuters) -CK Hutchison ( CKHUF ) confirmed on Thursday that Italian billionaire Gianluigi Aponte's family-run MSC Mediterranean Shipping Company is the main investor in a group seeking to buy 43 ports from the Hong Kong conglomerate.

Hutchison co-managing director Dominic Lai was speaking at the company's annual general meeting following weeks of scrutiny and criticism in China of its proposal to sell most of its $22.8 billion global ports business to a consortium led by U.S. investment firm BlackRock ( BLK ).

When asked if the Swiss-headquartered MSC shipping empire, which is controlled by the Aponte family, was the major investor, Lai said: "Yes, it has been from the beginning."

CK Hutchison ( CKHUF ) has not previously disclosed the exact ownership of each investor in the consortium.

MSC did not immediately respond to a request for comment on Lai's remarks.

The sale of assets, which would include two ports along the strategically important Panama Canal, has become highly politicised at a time of intensifying U.S.-China trade tensions.

In April, China's top market regulator said it was paying close attention to CK Hutchison's ( CKHUF ) planned sale and that parties to the deal should not try to avoid an antitrust review.

CK Hutchison ( CKHUF ), controlled by tycoon Li Ka-shing, said this month that the deal would strictly adhere to all required compliance standards.

The proposed sale has also drawn the attention of U.S. President Donald Trump, who has repeatedly expressed his desire to reduce Chinese influence around the Panama Canal and termed the deal a "reclaiming" of the waterway.