The Dutch Finance Ministry informed members of Parliament in a letter on Monday about "unauthorized access" to several of its banking systems, including the digital portal for treasury banking.

"Because of the ongoing forensic investigation and for security reasons, several systems have been temporarily taken offline, including the digital portal for treasury banking," Finance Minister Eelco Heinen wrote in the letter.

Heinen warned that the cyberattack has resulted in "around 1,600 public institutions that hold their funds with the Ministry of Finance" being "currently unable to view the balance of their treasury accounts digitally."

He continued, "Participants in treasury banking include, among others, ministries, agencies, legal entities with a statutory task, educational institutions, social funds, and decentralized governments."

"It is also temporarily not possible for participants to apply for loans, deposits, or credit facilities through the portal, change the intraday limit, or generate reports," Heinen warned.

Heinen admitted, "At this time, it is not yet known how long this situation will last."

He said investigations are ongoing in unison with the National Cyber Security Centre and other forensic security experts.

Heinen did not comment on who the responsible actor or actors were, or whether any ransom was involved.

To sum up, with the digital portal for treasury banking down, day-to-day cash management for a large swath of the Dutch public sector appears inaccessible at the moment.

So what happens if the portal stays offline long enough that the Dutch government cannot pay its bills?