LONDON – The European Union said it is probing a “potential leak of sensitive information” following a New York Times report that EU diplomatic cables were hacked.

The EU Council Secretariat insisted it takes the security of its IT systems “extremely seriously.”

European Commission Vice President Valdis Dombrovskis told reporters he would not comment on leaks.

“All communication systems have vulnerabilities, so we’re constantly dealing with this challenge,” he said.

The Times was allowed access to some 1,100 EU diplomatic cables by the “Area 1” security firm, a California firm that discovered the hacking. The “phishing” apparently occurred over a three-year period, beginning in 2015.

The firm believes that a Chinese unit was responsible. It told the Financial Times that the hackers took advantage of a weak link in the Cyprus Foreign Ministry.

The cables revealed inside information about what EU officials are thinking about President Trump, Russia’s moves in Ukraine, China, the Iran nuclear deal, as well as day-to-day diplomacy.

The cables are not highly classified and the information breaks little new ground. But experts say the security concerns are real.

One document appeared to capture a senior European official in Washington recommending that envoys from the EU’s member nations work around Trump by dealing directly with Congress.

In another apparent message, European diplomats described a recent summit between Trump and Russian President Vladimir Putin in Helsinki, Finland, as “successful (at least for Putin).”

Includes reporting by The Associated Press.