The Limburg politician insists that this is the only way in which root-and-branch reform can be introduced and Belgium's public finances can be made sound. Mr Dewael says that Belgium's current form of federalism more closely resembles a fight.
"As things stand, we won't succeed. The Flemish Government prefers to spend the cash itself than to make an extra effort to make Belgium's public finances sound. It's as if Flemings are not Belgians!"
"This is why I'm calling for the parties that form the Federal Government also to be represented in the regional governments. We can only press through all these reforms and make our public finances sound if all noses are pointing in the same direction."
"There is room for us. There are nine Flemish ministers. By law this can rise to eleven. It's completely justified."
Mr Dewael did not mention the fact that the Flemish nationalist N-VA that is a Flemish Government party is no longer involved in the federal talks.
The Flemish Prime Minister, Kris Peeters (Christian democrat), is not minded to respond favourably to Mr Dewael's request: "I can understand Open VLD's request, but in 2009 we agreed a coalition agreement for a five year period and we intend to complete the entire term with the same government parties."
Mr Peeters denies the idea that federalism in Belgium has become more of a battle than anything else. He insists that the Flemish Government has drawn up a balanced budget and is making its contribution to the federal finances.
The Flemish nationalist Deputy Premier Geert Bourgeois isn't impressed either: "I understand that the liberals are in a difficult position. Five months after the semi-theatrical appeal by the monarch the federal formation talks have led nowhere. This is a manoeuvre to draw away attention."