WASHINGTON, May 26: The US Senate has passed a broad immigration reform bill which opens the door to citizenship for at least 10 million illegal immigrants living in the country.

The bill, approved on Thursday in a 62-36 roll call, exempts businesses that have hired illegal workers from penalties and adds 370 miles of triple-wire fencing and 500 miles of vehicle barriers for sealing the US-Mexico border. It calls for deploying 3,000 border patrol agents on the border this year.

Although Mexicans are the main beneficiaries of the bill, it will also help thousands of other illegal immigrants from countries like Pakistan.

The leaders of both Republican and Democratic parties hailed the passage as a historic success. Majority Leader Bill Frist said the vote represented the ‘very best’ of the Senate. “This is a success for the American people. It is a success for people who hope to participate someday in that American dream,” said the Republican lawmaker.

Opponents said the Senate was ignoring clear public will and that the bill would have disastrous consequences for decades to come. “We will never solve the problem of illegal immigration by rewarding those who break our laws,” said Sen Jim DeMint, South Carolina Republican.

Mexico, however, praised the US Senate for passing the bill. Mexican President Vicente Fox, on a four-day trip to the US, said this was “a moment that millions of families have been hoping for”.

The bill is backed by President George W. Bush but will have to be reconciled with measures approved by the House of Representatives last year that would criminalise illegal immigration and impose tougher enforcement measures.

House Judiciary Committee Chairman James F. Sensenbrenner Jr, a Republican from Wisconsin, has been tasked to negotiate a compromise between the two chambers of the US Congress.

In a statement issued on Friday, he acknowledged it was difficult to forge a compromise between the very different House-passed and Senate-passed immigration reform bills and said that the bill approved by the Senate was unacceptable to the House of Representatives.

He said the Senate bill fell short on the two most important provisions of immigration legislation: securing the borders and enforcing sanctions against employers of illegal workers.

Mr Sensenbrenner said polls showed that the public preferred the House’s get-tough approach to the Senate’s way of dealing with immigration. But anything, he said, would improve upon the present system, which he called ‘the worst of all possible worlds’. “We have an obligation to try and work something out,” he said of the coming effort to reach a compromise with the Senate.