U.S. President Barack Obama is expected to focus on the nation's fragile economy and job creation, in his annual State of the Union address before a joint session of the Congress Tuesday night.

Senior administration aides say Mr. Obama will urge lawmakers to approve legislation to invest in a number of projects to boost the economy, including infrastructure, research and education. The president is also expected to link the economy with the issue of climate change with a call for spending on clean energy projects.

Mr. Obama will urge Congress to pass legislation on two issues currently under debate on Capitol Hill: gun control and immigration reform.

Sources close to the administration say the president will also announce the start on negotiations on a free trade agreement between the United States and the European Union. The 27-nation E.U. is the United States' largest trading partner.

And, The New York Times reports Mr. Obama will propose dramatic cuts in the world's nuclear arsenals. The newspaper says the president will build upon an agreement he has reached with the Pentagon to reduce the number of U.S. nuclear weapons from 1,700 to slightly more than 1,000.

After the speech, Florida Senator Marco Rubio will deliver the Republican response.

Under the U.S. Constitution, the president is required "from time to time give to Congress information of the State of the Union and recommend to their Consideration such measures as he shall judge necessary and expedient."