The New York Stock Exchange (search) is in talks with its members over extending its hours but has not decided on how much extra time it might add, the head of the exchange said Thursday.

NYSE Chief Executive John Thain (search) had said Wednesday that the NYSE was considering extending its trading hours. He added that the subject was "controversial."

Asked about expanding into Europe, Thain said the NYSE's focus for 2005 was in the United States. He also ruled out any bid for the London Stock Exchange (search), which is currently being courted by the Deutsche Boerse and Euronext exchanges.

In the United States, the NYSE can grow by expanding its product portfolio, Thain said. He said trading in options and derivatives are growth areas and "there are opportunities for us to trade related products."

Becoming for-profit and going public could carry some disadvantages, Thain cautioned.

"The potential conflict between lowering costs for our users and making money for shareholders is the big issue," he said.

Thain also said he supported remarks made this week by Securities and Exchange Commission (search) Chairman William Donaldson that it would consider giving foreign companies more time to meet a U.S. deadline for reviewing their internal accounting controls.

New listings of European shares on the NYSE have fallen amid companies' concerns about new regulations under the Sarbanes-Oxley Act (search), which came into effect after the corporate scandals in 2002 and 2003.

"I think the fact that the chairman of the SEC is publicly on record for being willing to address these ... important issues is a big plus," Thain said.

He acknowledged U.S. securities regulations have become more strict than Europe's, which he described as a "regulatory arbitrage." But he expects Europe will raise its corporate-governance standards, closing the gap.