Castex, a right-wing technocrat, was named prime minister last month in a cabinet reshuffle by President Emmanuel Macron. Before his appointment, Castex masterminded the plan that took France out of lockdown.He faces a delicate August in the frontline of the health crisis, with Macron decamped for his annual holiday at the Fort de Bregancon presidential retreat in the south of France. The country has emerged relatively swiftly from a two-month lockdown imposed to combat the virus, but this has come with the risk of an increase in cases. France, which has registered over 30,000 deaths from the COVID-19 epidemic, recorded thousands of new confirmed infections last week, prompting some regions to reimpose local restrictions.”We are seeing an increase in the figures for the epidemic which should make us more attentive than ever,” Castex said.”I call on every French person to remain very vigilant. The fight against the virus depends of course on the state, local communities, institutions, but also on each of us,” he added. Topics : Prime Minister Jean Castex on Monday urged France “not to let down its guard” in the fight against the coronavirus in order to prevent a new national lockdown, as concern grows over a surge in cases.”The virus has not gone on holiday and neither have we,” the premier said on a visit to the northeastern city of Lille.”We need to protect ourselves against this virus, without putting a stop to our economic and social life, in other words avoiding the risk of a new generalized lockdown.” Outdoor masks obligatory The city of Lille, a bustling hub close to the Belgian border, has been the subject of particular concern with the prevalence of the virus doubling to 38 people per 100,000 in just two weeks.In parts of the city it is now obligatory to wear masks outside to limit contagion, a move that local authorities in France can decide themselves.Outdoor mask-wearing has also been made mandatory in parts of the northern region of Mayenne, as well as the popular coastal holiday destinations of Biarritz, Saint-Malo and Le Touquet.The mayor of the southern city of Nice, Christian Estrosi, announced Monday that masks would be obligatory on some streets, including the busiest ones by the Mediterranean Sea.Asked how long the measure would remain in force, he replied: “Until someone tells me that the virus is not circulating.”Police were already out on the streets of Nice to enforce the new rule, but fines for not wearing masks — which can go as high as 135 euros ($158) — will only be imposed from Wednesday.The French government has encouraged citizens to go on holiday this year, especially within the country, in the hope of giving some help to an economy that contracted by a whopping 13.8 percent in the second quarter.But officials are keenly aware that opening up brings risks, and the government has been troubled by scenes especially of young people partying at close quarters outdoors in holiday spots.