Dame Barbara Stocking, Chief Executive of Oxfam, has set out her priorities for the London Summit in answers to questions submitted by viewers of Yoosk, the online interactive interview magazine.

In the first clip, a viewer asks Dame Barbara what Oxfam means by its call for the G20 countries to invest in a low carbon recovery. She replies that any fiscal stimulus should be used to make a difference on climate change, and commends the call by Professor Nicholas Stern, the economist, for 20 per cent of any new jobs to be in renewable or green energy projects. A second viewer then asks whether Dame Barbara is optimistic about the outcome of the London Summit. She says she is 'moderately' optimistic, because it involves a wider range of countries than the rich members of the G7 - but adds that it is important that the G20 members do not forget about the needs of the poorest countries.

• The London Summit agenda

A Yoosk viewer asks whether the IMF needs reform to make it democratic. Dame Barbara replies that she believes it needs substantial reform, right up to board level. Its leaders should also be chosen on merit rather than by country of origin. 'The IMF has an important role to play in the economic crisis,' she adds.

• Reform of the IMF

Dame Barbara is then asked whether the G20 countries should increase their taxes to ensure that there is no decline in spending on essential services. She says the main challenge is to curb the tax havens that siphon money out of poorer countries - and says she hopes the London Summit will close them down.

• The need to curb tax havens

Finally a questioner from Jakarta, capital of Indonesia, asks what actions the G20 countries could take to end world poverty forever. Dame Barbara says the global crisis is hitting the poorest people hardest, and it is important that the countries at the London Summit focus on maintaining the flow of aid they have already promised. 'But I’m very optimistic,’ she concludes.  'I think you can end poverty in the world.'

• Ending world poverty

You can see all the Yoosk questions answered by Dame Barbara on our London Summit YouTube channel.