The number of confirmed infections in Italy also increased to 9,172, up from 7,375 on Sunday, official figures show.
Italy is the worst-hit country after China, with cases of the virus confirmed in all 20 Italian regions.
Earlier on Monday, six inmates died amid riots at prisons across Italy after authorities suspended all visits.
Italy's government has pledged to further increase spending to offset the economic impact of the outbreak as the country struggles to adapt to the most restrictive limits on movement since World War Two.
Up to 16 million people in northern Italy now need permission to travel under quarantine rules.
In an interview with La Repubblica newspaper on Monday, Mr Conte said: "These days, I have been thinking about the old speeches of [Winston] Churchill - it is our darkest hour but we will make it".
The coronavirus causes the Covid-19 disease. In severe cases, patients have pneumonia, severe acute respiratory syndrome, and multiple organ failure that can lead to death.