"It was a dream landing," said NASA spokesman Rob Navias, adding that the astronauts' anxious colleagues on board the ISS already knew the landing was successful.

The Soyuz TMA-2 craft landed on schedule at 05:41 am Moscow time, in a secluded spot some 35 kilometers (21 miles) south of the town of Arkalyk, said the chief of Russia's space search and rescue agency, General Vladimir Popov. The vessel had undocked from the space station at 02:17 am (2317 GMT Monday).

"The cosmonauts feel fine. Pedro Duque was only sorry that his trip was so short," Popov said.

Duque, the first Spaniard to board the ISS, heartily agreed as he drank mineral water and munched on a huge apple, while Russia's Malenchenko opted for tea.

"The landing was so smooth, almost like it was in simulation," Duque said in Russian.

"It is great to be back home," said Lu, before the three astronauts were hustled off to a mobile hospital for tests.

However, the celebratory mood soured shortly after when heavy fog and a blizzard above Kazakhstan's capital Astana forced all of the rescue party's 11 helicopters to land in Arkalyk.

Doctors said the three astronauts, who were due to leave for Chkalovsky airport near Moscow later in the day, felt fine and needed no more medical attention than had been provided on the ground.

"The cosmonauts are in a good state and do not require any additional medical procedures," said Dr Nikolai Filatov of Russia's cosmonaut training center.

In an unprecedented security measure, doctors from the United States and Spain were present at the landing site, while 12 helicopters and three airplanes patrolled the skies.

A US military mobile hospital also was on standby in Kazakhstan's capital Astana, to ease concerns voiced by NASA and the European Space Agencyfollowing the last mission's troubled landing in May.

ESA is one of the main partners along with Russia and the United States in the 16-nation ISS project.

It is the first space mission for a European astronaut on the ISS since the disaster of the American space shuttle Columbia in February, and the presence of Spaniard Duque on the flight was seen as a boost for the European space program.

During his 10-day mission Duque carried a series of experiments in the fields of life and physical sciences, Earth observation, education and technology.

Malenchenko and Lu, who spent six months on board the ISS, were replaced by British-born American Michael Foale and Russian Alexander Kaleri, who will stay on board the space station until April 2004.

SPACE.WIRE