Rights activist Graca Machel, the wife of Nelson Mandela, bemoaned a lack of urgency in finding ways to save the three million babies who die each year in their first four weeks of life.
"Up to two-thirds of new born deaths can be prevented," Machel told the first global newborn health conference, adding that the measures needed were often both simple and cost-effective.
Most of these babies die from preventable conditions linked to inadequate healthcare for both the mother and child in poor countries.
Despite years of debate on the subject, "what has not been changed is our attitude -- to act with urgency, not as business as usual," said Machel.
Gary Darmstadt, director of family health with the Bill and Melinda Gates Foundation, said that despite increased levels of knowledge about baby deaths, newborns continue to die.
"The answer is pretty simple. We're not taking full advantage of the promising interventions we have at our disposal," he told the conference.
According to the UN children's agency UNICEF, newborn mortalities have grown as a percentage of child deaths from 36 percent in 1990 to 43 percent in 2011.
The heaviest neonatal deaths are recorded in South Asia and Sub-Saharan Africa.
"The number of newborns who die in sub-Saharan Africa has actually gone up in recent years, even while child and maternal deaths have fallen," said Darmstadt
UNICEF's Gupta said a big drop in mortalities was being targeted.
"We would like to see considerable shift in numbers by 2015. So we have 1,000 days to really make a dent in the numbers in a big way," she told AFP.
A recent study by the London School of Hygiene and Tropical Medicine has shown that in Africa, Rwanda has been the best performer in reducing deaths by 6.2 percent per year.
The worst performer was the continent's most populous state Nigeria which has a quarter of a million newborns dying annually.
"If you look at (Nigeria's) income growth and potential for change, there is really a disappointment with what could have been done and what so far hasn't come to play," the school's Joy Lawn told AFP.
In 2011, nearly 6.9 million children died before the age of five of which neonatal deaths made up three million.
The top causes were complications due to pre-term births and during the actual birth and poor care for mothers.