A free trade agreement between Morocco and the United States has come into immediate effect.
Morocco and the US have become close allies
The US House of Representatives gave its final approval on Thursday. It is the first trade agreement the US has signed with an African country.
Last month Morocco was designated a major non-Nato US ally by President Bush, in recognition of the country's support in the US-led war on terror.
US farmers are expected to be one of the biggest beneficiaries of the deal.
"This free trade agreement... signals our commitment to deepening America's relationship with the Middle East and North Africa," US Trade Representative Robert Zoellick said in a statement.
The deal eliminates more than 95% of tariffs on consumer products and industrial goods, other tariffs will end in nine years.
Last week Morocco hosted a major Nato military exercise involving naval and air forces from 10 countries; Morocco was the only non-Nato member taking part.
Morocco has increased its co-operation in fighting terrorism with Spain following the Madrid bomb attacks that killed 191 people.
Fourteen of the 18 people provisionally charged in connection with attacks on trains were Moroccans.
The Moroccan authorities have arrested about 2,000 people in cases linked to terrorism since it was hit by a suicide attack in Casablanca last May.
About 45 people, 12 of them bombers, were killed.
However, human rights groups have said that the anti-terror measures have eroded human rights and that suspected Islamists have been tortured by security agents.