Mexico City  - An estimated 500,000 truck and bus drivers in Mexico were on a 24-hour strike starting Monday, demanding the government freeze diesel prices.

Regional authorities in the states most affected by the strike tried to maintain a skeletal bus service so as not to inconvenience commuters. Private buses were allowed to operate as public transport vehicles.

The strike wreaked havoc in many Mexican cities, although it did not affect the bus and truck traffic in the capital, Mexico City.

Transport unions claim that 82 per cent of Mexico's trucks and buses use diesel. They said the price of diesel rose 27 per cent in 2008. (dpa)