From September 25 to 27, leaders from around the world met in New York and adopted the Sustainable Development Goals (SDGs), an ambitious 17-point agenda meant to transform the world by 2030.

The SDGs propose an integrated approach intended to end poverty, protect the planet, and achieve widely shared prosperity. The nearly 200 United Nations member states will be asked to implement policies to achieve the SDGs over the coming 15 years.

The new targets replace eight Millennium Development Goals (MDGs) adopted by the UN in 1999, as a guide to member nations' policies over the time frame of 2000 to 2015.

Achim Steiner, executive director of the United Nations Environment Programme (UNEP), believes the ongoing refugee crisis in Europe could be an incentive to trigger robust action on the SDGs. Reporter Nádia Pontes interviewed Steiner for Deutsche Welle on the margins of a conference in Brazil.

Deutsche Welle: The Sustainable Development Goals agenda is revolutionary. But it could mean a shift in the global order, since the SDGs are about equality, and social and environmental justice. How has the developed world been reacting so far?

Achim Steiner: I believe all countries support the SDGs. This agenda is important to Europe, the United States, China and everyone else.

It's clear to everyone the current development model needs to change. Looking around, we see crisis in so many different countries: unemployment, poverty, pollution, depletion of natural resources. These crises are not distant, as they once seemed to be. What happens thousands of kilometers away can indeed impact nationally.

Climate disasters, wars and refugee crises show how interconnected the world's challenges are, says UNEP chief Achim Steiner

The current refugee crisis shows this very well. Desperate people fleeing from war and struggling to survive are unstoppable. They're capable of walking thousands of kilometers. Nothing can stop their search for a safer place. This situation shows the entire world we need to act collectively.

What are the factors driving refugee crises?

UNEP studies have shown that not only wars, but climate change and major environmental problems will further force people to flee their homes, their countries. Syria, from where most of the refugees arriving in Europe come, suffered a severe drought for four years. The war aggravated this situation.

We're witnessing record numbers of people being forced to flee from conflicts, natural disasters and economic deprivation. According to the UN Refugee Agency, there were almost 60 million refugees in 2014 - the highest ever recorded. But as rising seas and escalating natural disasters wreak worsening havoc across the world, the number of people displaced from their homes may one day dwarf the magnitude of the crisis in Europe now.

So I think the current crisis could motivate countries to adopt the SDGs seriously.

How could the world achieve the SDG goals? What are the concrete plans?

The UN cannot create a foolproof plan that applies to all countries. Every nation, within its abilities and according to its reality, is encouraged to walk this pathway to achieve the targets. We want to inspire governments to act - but also civil society and business sectors.

We need, for example, to reduce pollution and increase mobility at the same time. So we need innovative technology. We may have to create new regulations. According to UNCTAD, we need investment of $5 to 7 trillion per year to deliver the Sustainable Development Goals.

Developing technology for green mobility is one way to achieve sustainable development

This is not a set of goals that basically assumes economic development comes first, and then you sort out your social, environmental and sustainability issues later. Leaders must develop policies for the new green, circular economy, and innovative financial instruments that foster prosperity and resource efficiency.

Brazil is dealing with a big political and economic crisis, the Chinese economy is also in trouble. How to convince those and other countries with emerging economies to think of environment and sustainability at this moment?

A lot of good things are happening. For instance, I'm in Brazil today to talk about new partnerships in the financial system. As one of the systems that ties our societies together, finance will be fundamental to the delivery of sustainability; and the banking sector in Brazil is very interested in taking part in this.

A significant portion of financial innovation and leadership is coming from the Global South. The People's Bank of China is a leader in green credit policies, and is by far the largest investor globally in renewable energies. India saw over 18 million bank accounts open in one week in that country's efforts to promote financial inclusion.

In 2014, other BRICS countries [Brazil, Russia, India, China and South Africa] were also among the top 10 countries investing in renewable energy, Brazil and India among them. Kenya, the African country where UNEP is based, is growing close to deriving 50 percent of its power from geothermal energy, and there are plans to host Africa's largest wind farm there.

Sometimes we tend to believe there is not much happening, but those figures show we have made a lot of advances.

How do you see the world in 2030?

I see a more stressed world. The world's population is projected to reach 8.5 billion by 2030 and 9.7 billion by 2050, which will increase the pressure on natural resources.

Done right, the work toward the SDGs can lead the planet and its peoples toward a more prosperous, sustainable future. But to be done right, the work needs to be done together… I'm optimistic that we can do it.

Interview: Nadia Pontes

Environmental expert Achim Steiner is executive director of the United Nations Environment Programme.