Fuel truck drivers gather during a strike action at the entrance of Aveiras Fuel Supply Station, Azambuja, Portugal on April 17, 2019 | Mario Cruz/EPA-EFE Portugal declares energy crisis as truckers’ strike cuts fuel supplies Government orders minimum services to keep airports, hospitals open.

LISBON – Portugal declared a national energy crisis Wednesday as a strike by fuel-truck drivers strangled supplies to gas stations, threatening to bring the country to a standstill.

The government ordered truckers to resume deliveries to airports, hospitals and other essential services and called in the security forces to ensure critical infrastructure is kept running.

Drivers from the National Republican Guard were reportedly taking 1 million liters of fuel to Faro airport in the south of the country Wednesday morning.

The government also ordered truckers to maintain services needed to keep the country’s two main oil refineries in operation and insisted “minimal” supplies of at least 40 percent of normal levels had to be maintained at gas stations in Lisbon and the second city of Porto.

“Supply to airports and to the security services is assured,” Prime Minister António Costa told parliament Wednesday. “We can also guarantee respect for the minimum supply of 40 percent at gas stations.”

However, as the strike entered its third day, hundreds of gas stations were running out of fuel and motorists lined up through the night to fill up at pumps that were still operating. Public transport operators in Lisbon and Porto cautioned they had only two days of supplies to keep buses running.

An unofficial website, set up to keep drivers informed, reported over 2,000 stations experiencing some sort of shortage, mostly of diesel.

The strike comes in a week where many Portuguese take to the roads for the Easter holidays, but union leaders vowed the walkout would continue until their demands are met.

“Until they meet with us and until we come to a conclusion, the strike will continue, and this critical situation will get worse,” warned Pedro Pardal Henriques, a lawyer serving as vice president of the union that called the strike on Monday.

The National Union of Dangerous Goods Drivers (SNMMP) was founded late last year. It claims to represent 700 of the around 1,000 drivers working in the sector and is demanding higher wages and recognition of its members’ special status.

“If we stop for two or three days, we throw Portugal into chaos,” António Medeiros, the union treasurer, told the Público newspaper. “We are perfectly aware of that.”

In an effort to mediate, the Socialist government held talks Tuesday with the union and the road haulage employers’ association, but failed to find a solution.

The SNMMP is one of a number of labor organizations founded recently outside Portugal’s main union structures, which traditionally have close ties to the left-wing political parties that support Costa’s government.

So far, the strike has little political support. “I’m not going to attack the government over something that isn’t the government’s responsibility,” said Rui Rio, leader of the main center-right opposition Social Democratic Party. He backed the government’s decision to demand that drivers maintain minimum services.