Guatemala's President Alvaro Colom has declared a "public calamity" from drought and famine that have claimed more than 460 lives since the start of the year.

"I have decided to declare a state of public calamity throughout the country," Colom declared in a nationally-broadcast address Tuesday.

"This will allow us to have access to international aid resources and to mobilize resources within our budget with greater ease," the Guatemalan leader said.

The country's health minister, quoted in daily newspapers here, said 462 people have died, including 54 children.

Most of the deaths occurred in the impoverished northern section of Guatemala bordering Mexico, where more than half of the 13 million inhabitants in the region subsist below the poverty line.

Key crops like corn and beans have been decimated by the drought, leading to a spike in rates of malnutrition.

Meanwhile, the drought also is being felt in neighboring Mexico, where the country's water commission last month warned of a "critical" water shortage that was likely to reach crisis levels by next year.

Mexico's Cutzamala reservoir which supplies the capital's urban sprawl is at record low levels, as are other public and private sources of water.

The drought, the worst in 70 years, is said to be caused in part by the "El Nino" seasonal warming phenomenon.