President Bush is challenging Congress on immigration reform.

He used his weekly radio address to step up pressure on Congress to embrace his idea for a guest worker plan for foreigners, while also talking tough about illegal immigration.

Bush calls illegal immigration a serious challenge and vowed, "We're going to protect our borders."

The president made appearances this week in Arizona and Texas that focused on border security and immigration, two items he says will top his legislative agenda next year.

His goal is to catch more foreigners crossing the border while increasing the number of temporary work visas for those who will take jobs that Americans are unwilling to fill.

The president is trying to appease social conservatives who take a hard line against illegal immigrants and business leaders who want to hire foreign laborers.