PALO ALTO, March 13 — The United States should rethink domestic and global financial regulation, Lawrence Summers (picture), director of the White House’s National Economic Council, said yesterday, outlining six “imperatives.”

“There is every reason to believe that pure market solutions are not viable,” Summers told a Stanford Institute for Economic Policy Research conference.

The speech comes against the backdrop of a debate over how much regulation and in what form would best cut risks of another Wall Street crisis or massive failure of the financial system.