China banned nearly 4,000 Party and government officials from joining more than 550 overseas group trips on public expense in the six months to the end of November, a top discipline official said Monday.

Ma Wen, deputy secretary of the Central Commission for Discipline Inspection of the Communist Party of China, said 830,000 official passport-holders went abroad in that period, down 18.9 percent year on year.

"Since the campaign was launched in last April, progress has been achieved in curbing overseas trips on public expense in China," Ma said at a video conference in Beijing.

Ma said the Central Commission for Discipline Inspection of CPC will work with the Foreign Ministry and other departments to strengthen supervision over government-paid trips aboard.

She said the tough penalties will be meted out to those who fabricate invitation letter to get approval by higher authorities.

Those who prolong the length of stay abroad or increase visiting places without authorization will also be punished, Ma said.

In December, China's State Administration of Foreign Experts Affairs (SAFEA) disqualified an American university from arranging government-paid training courses.

The Northwestern Polytechnic University, based in Fremont, California, has been found to provide an "unfaithful schedule" for officials from Wenzhou City of east China's Zhejiang Province.

At the end of last Nov., two officials in east China's Jiangxi Province were sacked and another one was given a disciplinary warning for attending a visit to the U.S. and Canada on public expense which was disguised as a study tour.

Editor: Yan