Washington - Seven new countries will be added to the United States' visa-waiver programme after meeting new security requirements aimed at reducing the threat of terrorism, President George W Bush announced Friday.

In about one month, citizens of the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Slovakia and South Korea will be able to visit the US for up to 90 days without obtaining a visa.

The admission was part of a long process that began some two years ago and has strained relations with US allies. Since the September 11, 2001 attacks on New York and Washington, the US has placed a variety of new security requirements on all foreign travellers.

Bush said he recognized the frustrations, but the measures were necessary to protect the US from terrorist attacks.

"In the world after September 11, we could only expand travel opportunities if we increased security measures at the same time," he said.

According to the new provisions, countries that are part of the visa-waiver programme need to issue tamper-proof biometric passports. Visitors will also need to register online with the US government before their travel as of 2009.

Bush called Friday's breakthrough a "new chapter in the relationship between the United States and your nations."

"Extending this opportunity to some of our closest allies deepens our friendship and makes all our countries safer," he said in a statement from the White House Rose Garden, joined by ambassadors from the seven countries, and six other potential candidates.

The announcement expands the US visa-waiver programme to 34 countries.

Six others - Bulgaria, Cyprus, Greece, Malta, Poland and Romania - are on track to join the programme at a later date.

Roger Dow, president of the US Travel Industry Association (TIA), said the announcement would help reverse a "significant decline" in travel to the US since the September 11, 2001 terrorist attacks.

In 2007, 2 million fewer people visited the US than in 2000, despite a weak dollar, according to the TIA. (dpa)