"I look at so many young people with the 12 stars lipsticked on their faces and I am troubled with the thought that people are beginning to have genuinely split allegiances", he wrote.
Verhofstadt will address to a joint committee of the Irish Parliament on Thursday and said he planned to meet business and community leaders in the Armagh-Monaghan border area.
He added that no hard border will be allowed but what should happen between North and South is a solution the British need to craft for a problem they created.
Mr Verhofstadt said the border between Northern Ireland and the Republic is in "no way a natural one".
The Dail has been given a commitment that Ireland will not be used as a bargaining chip in the EU/UK Brexit negotiations. "The European position ís the Irish position".
"The solution for this problem [Irish border] is entirely a responsibility for the United Kingdom government", he said.
Mr Verhofstadt also said protection of the Good Friday Agreement had not been sufficiently considered in Britain.
Marine Corps welcomes its first female infantry officer
Most of the course takes place in Quantico, Va., and that's where a celebratory "warrior breakfast" will be held Monday. Marine officials have argued those sentiments have waned in the last few years, but it's unclear how much.
"In my opinion this can only be a unique solution".
Mr Verhofstadt said peace in Northern Ireland is not just an Irish success but also an European Union success.
The key player in the European Parliament dismissed the Foreign Secretary's blueprint for exiting the bloc as nonsense and described his attitude as out of date. Invited to address its plenary May politely refused, a move taken as a snub - especially in the light of her speech in Florence tomorrow.
She said: "At least he'd had the manners to come and to talk to people about the implications which is far more than any British person has done".
I have seldom heard such nonsense and hypocrisy from European Union fanatics, like Mr Verhofstadt, over the Irish border.
In a video recorded by the European Parliament Information Office in Dublin, he said the post-Brexit border arrangement was a key concern for the European Union that needed to be quickly resolved. The resolution will also outline the European Parliament's priorities with regard to Ireland/Northern Ireland and assess the situation on the financial settlement.