He called on the participating world leaders to send "a strong message about our will to achieve" the MDGs by their target date of 2015.
"We must do it, we want to do it and we can do it," Deiss said. "We do not have the right to fail. The eyes of the world are upon us."
Deiss said the global financial crisis that began in 2008 had undermined progress towards the MDGs in many countries, but he emphasized that the preceding years of strong economic growth indicated the underlying potential of the world economy.
"We must be confident; we have the know-how and the resources to succeed, and we can do it. But that requires commitment from the donors and commitment from the beneficiaries, leading to a genuine partnership. This partnership must also include civil society and the private sector," he said. "If we want to succeed, we have to do it together."
World leaders and other senior government officials are addressing the high-level meeting over the next three days and also holding round-table discussions to examine how they can focus their efforts over the next five years to try to reach the Goals.
When delivering his statement at the General Assembly meeting, Bhim Bahadur Rawal, the minister for home affairs of Nepal, said that the least developed countries (LDCs) require effective international cooperation to meet the Millennium Development Goals (MDGs).
A "high degree of vulnerability" and "deep structural constraints" make it difficult for LDCs to reach the MDGs, he said. "Therefore we wish to underline that the international community should fully take this into account and give priority consideration to them, while making decisions on international support measures, including resource allocations."
Accelerated progress towards the MDGs, especially for the LDCs, can be catalyzed by stronger partnerships for development, Rawal said.
Positive response
For his part, French President Nicolas Sarkozy said that with only five years left to reaching the target date, world leaders must meet their commitments and accelerate efforts.
Sarkozy expressed his conviction "that while all developed countries are in deficit, they must find new sources of funding for the fight against poverty, for education and for solving major health problems in Africa."
"We have no right to do less. And the decision we make, we hope that all developed countries agree to do more and do it naturally as a priority for Africa," he said.
At the same time, Turkish President Abdullah Gul, in his speech at the MDGs summit, said, "Our focus is particularly on the least developed countries," he said. "We concentrate mainly on small and medium scale projects as well as technology and know-how transfer. "
"We have to think about achieving the MDGs in a more strategic manner by starting with setting some goals, for example, the eradication of extreme poverty and hunger as an immediate target," Thai Foreign Minister Kasit Piromya told the high-level meeting. " Achieving some goals first can ease the way to achieve the other goals and this makes achieving the MDGs more attainable."