(Corrects name in first paragraph from AIG International)

GREENWICH, Conn, Sept 16 (Reuters) - Ailing U.S. companies such as big insurer American International Group Inc AIG.N should seek financial lifelines abroad since they are as important to the global economy as they are within the United States, former New York City Mayor Rudy Giuliani said on Tuesday.

“AIG may ask China for help,” Giuliani, who sought the 2008 Republican presidential nomination, said at a hedge fund conference here.

Giuliani made the comments as Lehman Brothers Holdings Inc LEH.N hurtles toward liquidation and as Merrill Lynch & Co Inc MER.N agreed to be bought by Bank of America Corp BAC.N, and as several other U.S. companies are suffering heavy stock market losses.

AIG shares were down nearly 45 percent at $2.63 in midday trading on the New York Stock Exchange as the company tried to cobble together a rescue plan that could give it access to up to $75 billion in additional funding.

“I would think that, for AIG especially, international help would not be unrealistic,” Giuliani said.

AIG’s roots date back to its founding as a small insurance agency in Shanghai, China, 89 years ago. And it was early in moving back into the Chinese market when restrictions eased on foreign companies doing business there.

Former Chief Executive Maurice “Hank” Greenberg, who ran AIG for 38 years before stepping down in 2005, said in a CNBC interview on Tuesday that the private sector should come to AIG’s aid.

He added that sovereign wealth funds could be among the candidates interested in working with the insurer, which does business in 113 countries and territories around the world.

Greenberg, in the televised interview, said AIG’s collapse could create “systemic problems” for global markets, that would take years to fix. (Reporting by Svea Herbst-Bayliss, additional reporting by Lilla Zuill; Editing by Andre Grenon)