Leading members of the U.S. Senate say they are redoubling efforts to pass a comprehensive immigration reform bill. Lawmakers spoke at the White House after a meeting with President Bush.

From left: Bill Frist, George W. Bush and Harry Reid

As lawmakers returned to work after a two week recess, President Bush called the Senate leadership to the White House to talk about immigration reform legislation.

He urged them to pass a comprehensive bill that enhances border security but also sets up a temporary guest worker program.

"It's important that we reform a system that is not working," said President Bush. "It is important that we uphold the values of the United States of America. It is important that we treat people with dignity."

But the president acknowledged drafting legislation to deal with this controversial issue is a difficult task. Some lawmakers want a crack down on the more than 11 million illegal immigrants in the United States, while others want to offer them a path to citizenship.

The president said he opposes any amnesty, but added he supports a program that gives guest workers a tamper-proof permit to take jobs employers cannot fill. And he sounded confident Congress will eventually back his approach.

"I strongly believe that we have a chance to get an immigration bill that is comprehensive in nature to my desk by the end of this year," noted Mr. Bush.

Work on an immigration reform bill stalled in the Senate earlier this month as members were preparing to head home for an Easter recess. But as they emerged from the White House after Tuesday's meeting, Senate leaders from both major parties sounded optimistic.

Majority leader Bill Frist said the Senate will renew work on the bill soon with the aim of passing legislation by the end of May. He predicted Republicans and Democrats will unite to complete a good piece of legislation.

"We will pass a bill that will be comprehensive," said Bill Frist.

The top Democrat in the Senate - Harry Reid - agreed. He has been blamed by the Bush administration for blocking progress on the bill. But he walked out of the White House with praise for the president.

"I have to pat the president on the back," said Harry Reid. "This was really, I thought, a good good meeting. He is for comprehensive immigration reform. He said he is and I believe him."

All those who spoke to reporters after the White House session from both major political parties sounded energized and hopeful that there can be a meeting of the minds in the Senate on this critical issue.

But the toughest task may lie ahead. If a comprehensive reform bill passes the Senate, it must be reconciled with the very different piece of legislation that cleared the House of Representatives late last year. The House measure focuses solely on border security, and declares illegal immigrants to be felons. Immigration advocates - who have been organizing demonstrations across the country - say they hope the Senate version will prevail.