Skanska AB reported record-high revenue of all kinds and improved construction margins for the first quarter of 2020. But trouble could be just ahead.

"The impact of COVID-19 pandemic is yet to be seen" and "currently it is very difficult to say how severe the impact will be and exactly how long it will last," said company CEO Anders Danielsson during its most recent briefing for investors on April 28.  "It is crucial for us to both protect the people and company, to protect the strong balance sheet and the good liquidity."

Skanska's Q1 results briefing fit the pattern reported by other companies: one last strong quarter and then a journey into the financial and operational unknown.

The Stockholm-based construction and real estate giant is a major building and heavy and highway prime contractor in the U.S. It also builds nonresidential projects in its home country and in Norway, Finland, Poland, the Czech Republic and the UK. Roughly half of the construction revenue is generated in the U.S.

The company's shares are listed on the NASDAQ Stockholm exchange and traded under the SKA B symbol. They closed at about $19.60 on the day of the investor briefing.

For Q1 2020, Skanska reported construction operating income of $58.9 million, up significantly from the prior year's $37.1 million, on $3.53 billion in revenue, compared to $3.59 billion the year before.

Danielsson said the first quarter proved the company is "on the right path" to improved profitability, with better construction margins. But he and the company described the market conditions as "rapidly deteriorating" with the future uncertain.

In all, 370 projects in all countries and markets are affected by "inefficiencies or shutdowns" related to the virus pandemic, the company stated.