By Gavin Stamp BBC News business reporter

Paul Wolfowitz has seen for himself the challenges African countries face

Paul Wolfowitz has earned plenty of goodwill in his first weeks in charge of the World Bank.

After taking the job in controversial circumstances, Mr Wolfowitz pledged that Africa would be the development agency's main focus under his leadership.

To reinforce this, Mr Wolfowitz chose a trip to Africa as his first foreign mission, ending a week-long tour on Sunday.

The trip contained moments of powerful symbolism, not least Mr Wolfowitz's visit to a memorial to the victims of the 1994 genocide in Rwanda, in which 800,000 people were killed.

The sight of the former Pentagon hawk embracing some of the children orphaned by the mass slaughter will have helped to soften his rather austere image.

Cotton question

However, it is on the World Bank's approach to the many obstacles facing Africa's economic development and not the images of the past week that Mr Wolfowitz will be judged.

It will encourage those looking for evidence that the World Bank agenda is not going to be diverted by what was very much the Bush agenda Razia Khan, Standard Chartered

In that respect, experts say they are cautiously optimistic that Mr Wolfowitz has grasped the scale of issues facing Africa and will fight for change on key issues.

"The implementation of policy is obviously important but so far, so good," says Razia Khan, chief African economist at the Standard Chartered Bank.

Mr Wolfowitz surprised some observers by explicitly criticising farming subsidies in developed countries - including the United States - which he said were hurting African producers.

This was a constant theme of Mr Wolfowitz's public remarks during the trip and an issue on which he pledged action at the World Trade Organization's summit in Hong Kong in December.

Ms Khan said she was encouraged by Mr Wolfowitz's willingness to raise the issue.

"Addressing the subsidy question is going to be key to any long term development plan for Africa," she says.

"There were concerns about what sort of World Bank president he would be and these comments will encourage those looking for evidence that the World Bank agenda is not going to be diverted by what was very much the Bush agenda."

Chance of progress

Alex Vines, head of the Africa programme at the Royal Institute of International Studies, says progress on subsidies was vital to major cotton producers such as Burkina Faso and Mali.

"He may well be able to make progress because of his relationship with the current US administration," says Mr Vines.

"The issue is very much about the US protecting its own production."

Mr Wolfowitz's trip was undoubtedly made easier by its timing, coming in the immediate aftermath of an historic deal to cancel $40bn in debt owed by 18 of the world's poorest countries.

African companies need access to global markets, Mr Wolfowitz says

He will be under pressure to use the agreement to build momentum behind plans to boost aid to Africa and improve its trading status with the rest of the world.

"This visit to Africa signals willingness from Mr Wolfowitz to listen to poor men and women in Africa," says Oxfam's Caroline Green. "However, it must translate into real changes in World Bank policy."

Carrot and stick

Mr Wolfowitz seemed willing to dangle the carrot of increased development aid to the continent during the trip.

However, he also made it clear that under his leadership, increased financial support would depend on progress in improving governance and rooting out corruption.

He will be more explicit about performance Alex Vines, Royal Institute of International Affairs

"Development isn't all about foreign assistance," Mr Wolfowitz emphasised during his trip to Rwanda.

"We have seen too many examples of where foreign assistance was wasted or went to Swiss bank accounts."

The debt cancellation deal may herald a new era in Africa's relationship with the rest of the world.

However, observers feel that Mr Wolfowitz's more stringent attitude to how African governments conduct themselves means that there will inevitably be winners and losers.

Mr Vines said it was no coincidence that the World Bank boss chose to visit countries such as Burkina Faso and Nigeria with an improving record on fiscal responsibility and transparency.

"He will be more explicit about performance," he says.