LOS ANGELES – Controversial plans to reform Utah's immigration laws have thrown the spotlight on the western US state's governor, whose signature is needed to bring the new rules into force.

Governor Gary Herbert is expected to ink the legislative bills passed by the Republican-controlled legislature last week after months of discussion and behind-the-scenes wrangling.

The new laws would notably create a state guest-worker program while giving police the ability to assist in immigration enforcement.

But Tea Party activists and some Republican delegates have condemned the guest-worker bill as an amnesty, and have vowed to drive Herbert from office in 2012 polls unless he vetos the reform package.

"It is outrageous that any lone state would attempt to pass radical amnesty legislation that has been rejected by Congress and a majority of Americans again and again," said William Gheen, head of Americans for Legal Immigration.

Hispanic groups want the governor to strike down the enforcement bill and have announced a two-week boycott of Utah businesses, beginning March 14.

Local and national groups on both sides of the immigration debate have threatened lawsuits to halt the reforms.

Breaking from the hard-line approach taken by Arizona, which passed a draconian enforcement law last year, the hybrid package recognizes the need to control illegal immigration and the demand for unskilled labor despite high unemployment nationally.

In framing the reforms, Utah lawmakers sought to protect the state economy and avoid separating families by deportation, while pushing a reluctant US Congress to deal with the problem of undocumented workers.

With federal Republicans clinging to enforcement-only policies, Americans have never had an appetite for solving the immigration problem through deportation, said Marissa Graciosa of the Fair Immigration Reform Movement.

But, she added, states cannot solve a federal problem. "The immigration system does not need 50 patches," she said. "It needs an overhaul that only Congress can deliver."

The guest-worker program would allow undocumented immigrants to work and live with their families legally in the state by paying fines of up to $2,500 and passing a criminal background check.

The program would need a federal waiver and start in two years. Federal law currently prohibits employers from knowingly hiring illegal immigrants.

The enforcement bill would require state and local police officers to verify the immigration status of anyone stopped or detained for a serious crime and allow them to question those stopped for lesser infractions.

Lawmakers removed an earlier Arizona-style provision to allow police to question immigration status based on "reasonable suspicion."

Another bill proposes a pilot program with the Mexican state of Nuevo Leon to bring migrant workers to Utah on two-year rotations.

Utah's fast-growing Hispanic community may include more than 100,000 undocumented workers in the state's tourism, agriculture and construction industries.

Costly boycotts of the convention and tourism business followed Arizona's law, currently on hold after the US Department of Justice charged it infringed on federal powers.

Some Republican politicians also worried that Arizona's law alienated Latino voters.