Illegal immigration could be encouraged given that relevant countries blindly believed stories made up by illegal immigrants and accommodated their pleas for "political asylum", said Foreign Ministry spokesman Zhu Bangzao in Beijing January 13.

Zhu made the remarks at a regular press conference in response to reports about illegal Chinese immigrants being detained by the US in recent weeks.

China has noticed such reports but has not yet received verified details, he said.

"We have consistently opposed illegal immigration and have taken a series of effective measures to curb it," he said.

China has enacted laws banning illegal immigration and tightened controls on its borders, according to Zhu.

"We have also kept up healthy consultation devices with relevant countries to deal properly with the problems of illegal immigration," he said.

However, some illegal immigrants tell lies and make up excuses in asking for "political asylum" or "refugee status", so as to ensure their stay abroad, Zhu noted.

If relevant countries are easily taken in by their tales and approve their application, it would be an encouragement to waves of more illegal immigrants, he warned.