Key technology executives had been pushing for changes to the immigration bill in the Senate to make it easier to hire foreign-born computer scientists and other skilled professionals before the compromise measure collapsed.

"We're hopeful the Senate will be able to find a way to get this process back on track," said Robert Hoffman, an executive at Oracle and co-chair of Compete America, a coalition of computer and electronics firms and other business groups focused on immigration.

"The issues we're facing on the skilled immigration front are so important, we hope the Senate will find a path forward."

Even as technology executives including Microsoft chief executive Steve Ballmer were furiously lobbying in the past week to modify the latest bill to provide more visas for skilled workers, the compromise immigration bill was withdrawn by Democratic Senate leader Harry Reid.

"At Microsoft alone we have 3,000 core technical positions we have not been able to fill in the United States because of the lack of available qualified applicants," said company spokeswoman Ginny Terzano.

Terzano said Ballmer met with lawmakers to discuss "the urgent need to fix the immigration system. if the high-tech industry in the US is going to be able to hire and retain qualified workers."

While Senate leaders and President George W Bush had warned against modifications to the fragile compromise on immigration reform, tech industry leaders claimed there were flaws in the latest measure that could make it even harder to attract top-flight professionals.

The bill as written, tech executives said, would have failed to provide enough relief for companies struggling to fill jobs. Some argued that the companies should have the same type of exemptions as major sports leagues, which can lure foreign-born players with special skills.

The high-tech industry says many of those working in the global-leading sector are immigrants themselves, including Google co-founder Sergey Brin.

Lazlo Bock, vice president for people operations at Google, told a congressional hearing Wednesday: "The US scientific, engineering, and tech communities cannot hope to maintain their present position of international leadership if they are unable to hire and retain highly educated foreign talent."

Some critics of the H-1B visa programme say it is used to depress wages in the tech sector, with the hiring of engineers from India and other Asian nations, and argue that evidence of a shortage is not entirely clear.

But Hoffman said multinationals such as Oracle and Microsoft are faced with a dilemma because of the visa shortage, and often must relocate those jobs offshore.