Juho Romakkaniemi, chief of staff to Commission Vice President Jyrki Katainen wrote on Twitter he said that he fears that discontent could lead to further splits as countries want to get more out of the bloc than they put in.
But despite concerns, Mr Romakkaniemi believes that the EU is “too big to fail”.
In a Twitter thread, the Finnish chief of staff argues that Central and Eastern European countries have unrealistic expectations of how the EU would improve their country after 40 years of political and economic strife.
He wrote: “Many thought that their country would catch up German living standards in a decade. Of course they didn’t.
“Even the Eastern part of German hasn’t come to same level with the west in 25 years despite even bigger aid.”
He suggested that there is bitterness from those countries as they get “more and more critical of the EU,” despite Poland Hungary and the Czech Republic being among the biggest net receivers of EU funding.
The 40-year-old also said that “too few” politicians throughout the bloc have embraced EU positive policies like French President Emmanuel Macron.
States have based their EU views and membership on what they could milk from it, rather than “what can we achieve” with the help of the union.
Something he said would be a “bad and dangerous development.”
Although he believes the EU is too big and powerful to fail, he thinks there are still risks to the stability of the bloc if leaders do not act.
He continued: “Peace is just too valuable for Europe and the world to be lost.”