Mr Cameron said both forums had vital roles to play - the G8 for consideration of big foreign policy and security issues and the G20 for discussing major economic issues.
The Middle East Peace Process, Iran and North Korea were under discussion at the G8, as well as international aid. Leaders signed up to the Muskoka Initiative - a $5 billion package of aid targeted at improving child and maternal health in poorer nations.
The PM said:
Today in the UK, the chances of dying in pregnancy and childbirth in one in 8,200. In parts of Africa it is as low as one in seven. This is something we can change - and we must change. And the resources agreed - including a big contribution from the UK - could lead to an additional 1.3 million lives being saved.
Commitments made at the G20 included an agreement for countries to halve their deficits by 2013 and a set of principles on bank levies. Mr Cameron said the Summit “specifically welcomed” the UK’s plans to cut its deficit set out in the Budget earlier this month.
He also reiterated the need for progress on the Doha Round, which he said could add $170 billion to the world economy.
The PM said:
In my view, too many people still see this as a zero sum game where one country’s success in exports is another country’s failure. This is nonsense. Everyone can benefit from an increase in trade flows. We will play our part in breaking the log-jam. I want this country to lead the charge in making the case for growing trade flows around the world.
The Prime Minister also held one-on-one talks with a number of his fellow leaders during the two summits, including US President Barack Obama, Russia President Dmitry Medvedev and Chinese President Hu Jintao.
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