Portuguese President Marcelo Rebelo de Sousa said on Friday he would propose next week extending a national lockdown till May 1 as the number of coronavirus cases in the country rose above 15,000.Parliament is likely to approve his request. Portugal declared a 15-day state of emergency on March 18 and last week approved its extension by a further 15 days till April 17."We have to be very focused on a fight that we haven't fully won yet," Rebelo de Sousa, who was himself in quarantine for two weeks last month despite testing negative for coronavirus, told a news conference. "We cannot let our guard down."Portugal has so far reported 15,472 confirmed cases and 435 fatalities, far below neighboring Spain's death toll of 15,843, the second highest in the world after Italy.Speaking at a morning show on TVI television on Friday, Prime Minister Antonio Costa said: "It would be a wrong signal for the country to lift the state of emergency.""There is still no light at the end of the tunnel," Costa said. "We have to walk through this tunnel and the more disciplined we are now the faster we will get to the end of it."Both Costa and Rebelo de Sousa said it was critical that the Portuguese stay home during the usually busy Easter period to avoid contagion.The government has tightened restrictions further over the Easter holiday period, closing all airports to commercial flights and banning domestic travel from April 9-13.