EU & Markets: Stocks in the U.S. are down more than 1 percent at the opening bell, following similar declines in Europe.
Big factors include weak economic news out of Europe and worries about Greece's debt crisis. Many investors in the U.S. are starting to believe the stock market has advanced too far, too fast this year.
The Dow Jones industrial average fell 143 points to 12,820 early Tuesday. The Dow has yet to close down 100 points or more any day this year.
The Standard & Poor's 500 index is down almost 15 points, to 1,349. The Nasdaq composite fell almost 31 points to 2,920.
France's main stock index fell 2.6 percent. Britain's FTSE lost 1.5 percent and Germany's DAX fell 2.5 percent.
Government: President Barack Obama is aiming mortgage relief at members of the military as well as homeowners with government-insured loans, the administration's latest efforts to address a persistent housing crisis.
In his first full news conference of the year Tuesday, the president will announce plans to let borrowers with mortgages insured by the Federal Housing Administration refinance at lower rates, saving the average homeowner more than $1,000 a year. President Obama also was detailing an agreement with major lenders to compensate service members and veterans who were wrongfully foreclosed upon or denied lower interest rates.
The efforts the president is announcing do not require congressional approval and are limited in comparison with the vast expansion of government assistance to homeowners that he asked Congress to approve last month. That $5 billion to $10 billion plan would make it easier for more borrowers with burdensome mortgages to refinance their loans.
Tech: Verizon Wireless on Tuesday announced a version of its wireless broadband service that's designed for use in rural and remote homes that can't get DSL or cable.
The service, called HomeFusion, could also appeal to some households where DSL is the only fixed-line option, since it's faster than most DSL services. HomeFusion could provide potent competition for satellite broadband providers, which are often "providers of last resort" for rural homes. The service requires the installation of a cylindrical antenna, about the size of a 5-gallon bucket, on an outside wall. The hardware costs $200, but the work is free.
Oil: Oil prices hovered below $107 a barrel Tuesday in Asia after U.S. and Israel leaders met to discuss growing tensions over Iran's nuclear program.
Benchmark oil for April delivery was up 13 cents to $106.85 at late afternoon Singapore time in electronic trading on the New York Mercantile Exchange. The contract rose 2 cents to settle at $106.72 per barrel in New York on Monday.
Brent crude was down 6 cents at $123.74 per barrel in London.
After a meeting Monday in Washington, President Barack Obama and Israeli Prime Minister Benjamin Netanyahu showed no sign of give on competing ways to resolve the crisis. Obama urged pressure and diplomacy to prevent Iran from getting a nuclear bomb while Netanyahu emphasized his nation's right to a pre-emptive attack.
The U.S., Europe, Israel and other nations fear that Iran may be building a nuclear weapon. Iran, the world's third-largest oil exporter, denies the charge.
"The Iranian fear premium didn't change in our view," energy consultant Ritterbusch and Associates said in a report.
Crude has risen from $96 last month amid investor concern that a military conflict aimed at destroying Iran's nuclear capabilities would disrupt global oil supplies. Analysts say Saudi Arabia and other oil producers do not have enough spare capacity to quickly make up for Iran's 4 million barrels a day of crude.
Analysts estimate crude would jump to $150 in the wake of an attack by Israel on Iran's nuclear operations.
"The risk of a supply disruption due to geopolitical factors is uncomfortably high and increasing," said Richard Soultanian of NUS Consulting.
In other energy trading, heating oil fell 0.2 cent to $3.22 per gallon and gasoline futures were up 0.2 cent at $3.26 per gallon. Natural gas fell 0.4 cent at $2.35 per 1,000 cubic feet.
The Associated Press contributed to this report