The United States is not protectionist and there is "no bias" against Italian auto giant Fiat's possible tie-up with Chrysler, US House of Representatives speaker Nancy Pelosi has said.

"President (Barack) Obama is not a protectionist president," Pelosi told a news conference in Rome during a visit to Italy.

Pelosi said US workers needed to be "assured that we're looking out for their interests as we look to grow the US economy," according to Agence France-Presse (AFP).

"I don't think that's protectionism. I think that's what any country would do for its workers," she added.

The report noted there had been widespread criticism from Washington's main trade partners of a "Buy American" clause in a massive new US economic stimulus plan that would favour the use of US-made iron, steel and manufactured products.

"Somewhere in the mix of things, someone has decided that America has become ... more protectionist," Pelosi said.

"I don't think that's the case. We want to go forward in a way that is good for workers across the global economy."

Referring to a possible deal between Fiat and Chrysler, she said: "There's no bias against Fiat because they're not an American company."

Chrysler has said its recovery plan - due with the government today (17 February) - would not be affected by an alliance announced last month with Fiat, which some analysts have said could complicate the private automaker's efforts to persuade reluctant lawmakers to extend more aid.