WASHINGTON -- President Barack Obama called Thursday for the country to move swiftly to a system of high-speed rail travel, saying it will relieve congestion, help clean the air and save on energy.

Appearing with Vice President Joe Biden and Transportation Secretary Ray LaHood, Obama said the country cannot afford not to invest in a major upgrade to rail travel. He said he understands it necessarily will be "a long-term project" but said the time to start is now.

The president allocated $8 billion in the enormous $787 billion economic stimulus spending package for a start on establishing high-speed rail corridors nationwide.

Obama said, "This is not some fanciful, pie-in-the-sky vision of the future. It's happening now. The problem is, it's happening elsewhere." He cited superior high-speed rail travel in countries like China, Japan, France and Spain.

The rail upgrades are critically needed, Obama said, because the nation's highways and airways "are clogged with traffic."

The money will go not only to high-speed rail development but also to a parallel effort to improve rail service along existing lines -- upgrades that would allow faster train travel.

The White House said funding will move into the rail system through three channels, first to upgrade projects already approved and only in need of funding, thus providing jobs in the short term. The second and third would focus on high-speed rail planning and then a commitment to help in the execution of those plans far into the future when the stimulus funds are no longer available.

Transportation Department officials say about six proposed routes with federal approval for high-speed rail stand a good chance of getting some of the $8 billion award. The spurs include parts of Texas, Florida, the Chicago region, and southeast routes through North Carolina and Louisiana.

The U.S. Federal Railroad Administration says the term high-speed rail applies to trains traveling more than 90 mph. The European Union standard is above 125 mph.

Many overseas bullet trains -- most powered by overhead electricity lines -- run faster than that. In France, for example, the TGV ("Train a Grande Vitesse") covers the 250 miles between Paris and Lyon in one hour, 55 minutes at an average speed of about 133 mph.

In Japan, which opened the first high-speed rail in the 1960s and carries more passengers than any other country, the Japanese Shinkansen trains hurtle through the countryside at an average of about 180 mph.

Super-fast trains also run in Germany, Spain and China, at speeds up to 140 mph, according to a 2007 survey in the trade publication Railway Gazette.

The only rail service that qualifies under America's lower high-speed standard is Amtrak's 9-year-old Acela Express route connecting Boston to Washington, D.C.

The trains are built to reach speeds up to 150 mph, but only average about 80 mph because of curving tracks and slower-moving freight and passenger trains that share the route. On the densely traveled line from New York City to the nation's capital, the Acela arrives just about 20 minutes earlier than standard service, at more than twice the cost during peak travel times.