Whilst visiting the awful slums in the heart of South Delhi and Kolkata on my recent visit to India with Save the Children, it was impossible not be shocked by the sheer scale of inequality in the country. In one of the slums, we saw people "rag-picking" - which to you and I means physically sorting through bags of rubbish - with children, many in bare feet, helping to sort through the refuse and filth in the most unspeakable conditions. A mere 50 yards away stood smart new apartment blocks - with a high metal fence separating the residents from their slum-dwelling neighbours. The contrast was stark.
India's economy is growing at a phenomenal rate and it feels like a country in a hurry. On his recent trade visit to the country, David Cameron said he wanted UK companies to help India develop new cities and districts, generating investment projects potentially worth up to $25 billion.
Some argue that all that is needed to tackle the awful poverty in India is simply to keep focus on growing the economy and that prosperity and opportunities will eventually "trickle down" to the poor. But from my experiences in India, I'm not convinced. The vast economic growth in recent times has been joined by growing inequalities of income and wealth, adding to existing inequalities between gender, class, tribal and religious groups.
Globally, we have made huge strides in tackling poverty through international development and foreign aid. Indeed, extreme income poverty has dropped from two billion in 1990 to less than 1.3 billion today. And incredibly, child mortality has almost halved in that time. But the gap between rich and poor children globally has grown by some 35 per cent.
The effect that this inequality has is devastating, especially for children, who are hit twice as hard by inequality, despite its causes not being of their making. Almost half of all children under-five in India are so malnourished that they are stunted - leaving them less able to fight off common and easily preventable illnesses such as diarrhoea and pneumonia.
When we visited Dhapadhipi, the awful slums in Kolkata, we saw how community health volunteers were measuring the arms of babies using a tape, developed by Save the Children, which had a simple colour-code for healthy, moderately malnourished and severely malnourished (green-amber-red). We met two year-old Pritam who was measured in front of us - his mother was delighted to see the measuring tape record green for healthy. Sadly, countless other mothers see red for severely malnourished.
Last year, 1.6 million Indian children died before their fifth birthday - almost a quarter of all global child deaths. And although people living in India make up 18 per cent of the world's population, it is home to nearly a third of those living with less than $2 a day.
On one of our visits in South Delhi, we met a family who lived in a small room that was about the third of the size of my garage back home in England. We spoke to Prashuram, who lives in the small room with his wife, their son, Rajkumar, their daughter in-law, Shalini, and their two grandchildren. The family, particularly the children, rely heavily on Save the Children for health and educational services. This was just one example of millions living in poverty across the country.
Save the Children rightly argue that tackling inequality is one of the most effective ways to accelerate reductions in global poverty. By returning to 1990 levels of inequality, India could reduce the numbers of people living on $2 a day by 240 million by 2030 - meaning India would be on track to completely eradicate this form of income poverty by the early 2030s.
But addressing inequality worldwide is not solely for the purposes of reducing poverty. In India, for example, there was massive social unrest over gender inequality recently after the lack of action following an abhorrent gang rape of a young female student on a bus. More unequal societies perform worse in terms of child development outcomes, it undermines peoples' sense of self-worth, weakens social cohesion and stifles economic growth. This is acknowledged by the IMF, which warned in a recent report that the "cost of high inequality to the wellbeing of society can be very high".
It is now clear, more than ever, that we need to tackle all forms of inequality in order to create fairer, safer societies for all, especially children. Some 70 per cent of the world's poorest people live in middle income countries and some large regions in India have similar levels of poverty and deprivation to the poorest African countries.
David Cameron, in his role as co-chair of the High Level Panel on the post-2015 development framework, has set the goal of eradicating absolute poverty by 2030. But it is clear that this will not be possible without a clear focus on reducing inequality.
A lot of good work has been done already, but what was made abundantly clear to me during my visit to India was that there is still so much left to do. And it shouldn't just be about the economy. It's the inequality, stupid, too.
Michael Dugher is MP for Barnsley East, Vice-Chair of the Labour Party and a Parliamentary Champion for Save the Children