KABUL, Afghanistan (AP) -- The U.S. government will spend $511 million to expand its embassy in Kabul, the U.S. ambassador said Wednesday, describing the work as a demonstration of America's long-term commitment to Afghanistan.

"We make this commitment by commemorating the recent award of a $511 million contract to expand the U.S. Embassy here in Kabul," Ambassador Karl Eikenberry said during a ceremony at the construction site that marked the formal announcement of the contract.

"We're going to get a day when that embassy's up and there's not going to be these barriers out there, there's no barbed wire, there's not going to be all kinds of obstacles out there," Eikenberry said.

Currently the road to the embassy, located in downtown Kabul, is blocked by large concrete barriers and the building is surrounded by armed security guards.

"This next generation of Afghans growing up, we hope that they come to this embassy, they're welcome here and this is going to be the new normal for Kabul," he added.

Eikenberry's remarks come amid Afghan concerns that the proposal to begin drawing down U.S. forces by July 2011 could leave Afghanistan alone to fight the Taliban insurgency.

Many Afghans felt abandoned by the U.S. after 1989, when the Soviet Union withdrew its army from Afghanistan and U.S. support to mujahedeen fighters dried up. The country sank into years of brutal civil war.

But Eikenberry used his speech to emphasize U.S. commitment to a peaceful Afghanistan, pointing out that the embassy has tripled its civilian staff in the past year. The new facilities will provide offices and living space for many of them.

The project started earlier this year and currently employs about 500 Afghans. Once construction gets under way, more than 1,500 Afghan workers will be employed, Eikenberry said.

Over the last two years, the U.S. has signed contracts to expand American diplomatic facilities in Kabul and consulates in Mazar-e Sharif and Herat provinces that total $790 million, he said. The figure includes the embassy expansion, which should be completed by June 2014.