Bachelet told reporters that more than 9000 firefighters and other responders have been enlisted to battle the fires, which have destroyed almost 1.2 million acres (480,000 hectares) in seven regions of the South American nation.
"We are fighting the fire without pause and without precedent," Bachelet declared.
More than 4500 volunteer firefighters and members of the country's national forest brigades plus some 4600 police officers and other public officials are battling the blaze.
The fires have forced more than two thousand people into shelters, and have damaged or destroyed more than 4000 dwellings.
Among the countries that have dispatched aid to help put out the infernos are Argentina, Spain, France, Portugal and Mexico.
A Russian aircraft with a 42-ton water-carrying capacity is due to arrive on Sunday, while Brazil and Peru were also expected to send firefighting aircraft.
According to the latest report by Chile's national forest service, Conaf, there are a total of 110 separate fires, 50 of which are under control, while 60 are still being fought.
Fires are common in Chile's parched forests during the southern hemisphere's summer. Most are caused by human activity. More than 35 people have been arrested and accused of playing a role in starting or propagation the fires.
Fire activity this year was worse than usual because of a drought attributed by environmentalists to climate change.
