The former Belgian Prime Minister, who is on his second trip abroad after his appointment on 19 November, added that the main principles in his work would be "dialogue, unity and action".
"This is not a usual day, this is a historic day," Pahor told the press after receiving Van Rompuy, who is formally assuming his post today.
"All of us who have European dreams are welcoming this day as a breaking point in the sense that Europe gets an institution which represents it both inwards and outwards", added the prime minister.
While noting that the capacities and powers of the new post were limited with the Lisbon Treaty, Pahor said that it was clear that Europe was getting a face.
He is convinced that Van Rompuy will be absolutely up to the task and that he will be able to slowly build the new European institution. Pahor also finds it important that someone with a feeling for social dialogue and social issues is at the helm of the EU.
Van Rompuy added that it was important that he and his colleagues from the European Council also discuss topical issues at informal level. "We will lend an ear to everybody so that everybody will benefit from our work."
He said he was committed to cooperation with the President of the European Commission, the European Parliament and the governments of member states. The official plans to pursue continuity and coherence.
Van Rompuy emphasised as key challenges the economic crisis and its impact on jobs, the "climate crisis", which requires success at the Copenhagen climate conference this month, energy issues and expectations of social justice.
The president of the European Council also touched on the border arbitration agreement between Slovenia and Croatia, assessing it as a very good example of how issues are solved in a European way.
This is a proof of political courage and leadership of both prime ministers, he said, adding that the agreement allowed Croatia to continue its EU accession talks, which is an important signal to Western Balkan countries.
Van Rompuy was also received by President Danilo Tuerk, who congratulated him on the appointment.
According to the president's office, Van Rompuy and Tuerk exchanged views on fundamental issues related to the future of the EU, which will demand coordinated work of all European institutions and inclusive political process.
The officials also discussed ways to consult on political issues in the future, including consultations on the future European security system and the situation in the Western Balkans.
Van Rompuy will depart today from Ljubljana to Milan, where he will meet Italian Prime Minister Silvio Berlusconi. In the evening, he is also to attend the ceremony marking the Lisbon Treaty's entry into force in Portugal.
