Adianto P. Simamora, Jakarta – Environmentalists say the removal of six billboards, which welcomed visitors to the "city of pollution", comes as a major setback for the Jakarta administration's clean air campaign.

Councillor Mukhayar, who is also deputy chairman of Commission D for environmental affairs, said he felt let down by the city administration.

"It's a real shame... Even without them, everybody knows how polluted Jakarta's air is. So why try to conceal the truth?" Mukhayar, who heads the Jakarta Environment Caucus, told The Jakarta Post on Thursday.

The billboards, designed by the Jakarta Environmental Management Agency (BPLHD) and clean air campaigner Swisscontact, were erected as a reminder to residents to get their vehicles' exhaust emissions tested.

One billboard was set up in each of the city's five municipalities and the sixth in front of the BPLHD office, for World Environment Day on Monday.

However, after just one day, Jakarta Governor Sutiyoso said the billboards were coming down. He provided no explanation, but some officials said the billboards were bad for tourism.

Ari Muhammad of Swisscontact said there was no logic to the notion. He said that residents, including officials, needed to look at the text for what it was. "It's self-criticism for the public... We have to take concrete action to improve the quality of city air, together," he said.

Sutiyoso has himself conceded Jakarta is the world's third-most polluted city, after Mexico and Bangkok, blaming it on unchecked exhaust emissions from vehicles and factories.

While promoting his idea of incorporating Bogor, Depok, Tangerang, Bekasi, Puncak and Cianjur into Jakarta, Sutiyoso claimed it would help to reduce air pollution. He promised to improve commuter linkages so that people were more willing to leave their cars at home.

Administration data shows that more than 2.5 million private cars, 3.8 million motorcycles and 255,000 public transportation vehicles traverse the city streets each day, and many of them come from areas outside Jakarta.

Jakarta is the first city in the country to have issued a local ordinance on air pollution control, which requires private cars to undergo emissions tests and public transportation vehicles and official cars to use compressed natural gas.

BPLHD head Kosasih Wirahadikusumah said his office was trying to get a permit from the governor, so that the billboards could be put back. "They won't be gone long," he told the Post.