BANGKOK, Jan. 15 (Xinhua) -- Bangkok's truckers have been advised to use biodiesel instead of regular diesel to help fight the city's air pollution.

During a meeting in Lampang province on Tuesday, Prime Minister Prayut Chan-o-cha called on motorists, especially those with diesel-engined trucks running on Bangkok's streets on daily basis, to turn from regular diesel to biodiesel.

Bangkok's air pollution has been worsened to an alarming level, prompting many pedestrians to put on cloth masks to protect themselves and the authorities to launch rainmaking operations in the sky.

The Ministry of Energy has readily obtained an adequate volume of biodiesel as fuel for cargo trucks plying the Bangkok streets, confirmed the prime minister.

Prayut said he has instructed the authorities to strictly see to it that any vehicles which might release black smoke through exhaust pipes will be immediately stopped from running.

The particulate matter in the city's air was reported to rise over 50 micrograms per cubic meter on Sunday, considered unhealthy to people, according to the Pollution Control Department.