The budget question seems set to dominate this week's Open Days in Brussels, where 6,000 regional stakeholders and policymakers will gather to discuss the future of the EU's regional policy.
As reported by EurActiv ahead of the October 2010 outline of the post-2013 EU budget, high-profile supporters of European regional policy are worried that regions will lose both funding and prominence in the coming years.
Hahn believes regional policy needs to keep its current funding levels - around one third of the EU budget - to make the Europe 2020 agenda a reality and "make Europe more visible" across the 27 EU member states.
The Open Days will also feature numerous debates on what the EU's regional policy will look like after 2013, when the new seven-year budget period starts.
The Austrian commissioner wants a more results-orientated policy, focused on fewer priorities but with greater flexibility in their implementation. As a result, these priorities will be better aligned with the 2020 strategy, allowing EU member states and regions to better integrate policies, he argued.
Hahn dismissed the possibility that the recent austerity cuts by the UK government, which axed a number of regional offices, were a sign that member states are de-prioritising the value of the regional and local level.
"As I understand, this approach by the new British government is to abandon local bodies at one administrative level, but the further implementation of projects should not be affected by that."
Likewise, he dismissed claims that, as commissioner, his strong emphasis on cities and urban policy would lead to an uneven balance in regional policy as a whole. In fact, Hahn believes the "urban dimension" has been far too overlooked in the current budget period (2007-2013), which is why he has fought for a greater emphasis to be placed on it.
Indeed, if his push for a great "re-urbanisation" succeeds, he said he will rank it among his greatest achievements.
As regards another key aim of his term, the simplification of EU regional funding rules, he believes the issue has already made great strides, notably thanks to the amendments brought by the European Parliament.
However, Hahn argued that "simplification does not always have to mean changing everything". In other words, if something is proven to be doing well, then it should be left alone and adjustments should only be made where necessary.
Likewise, Hahn blamed national rules for many of the problems. "I must say that some of the burdens are due to national regulations," he said, before conceding that "things are moving in the right direction" and improving in general.
Finally, the Austrian commissioner said he fully supported so-called 'Objective 2' regions which fear they will lose regional funding after 2013 when poorer Eastern EU countries will get full access to EU funds. Ahead of the Open Days, 141 regions whose GDP is close to the EU average but which still face development obstacles have urged EU leaders to protect their status under the new policy.
"I have always supported them," Hahn replied. "As I said in my hearing, I stand for regional policy covering the entire EU as an investment policy and so fully support the initiative," he said.