Image copyright Getty Images Image caption The US-Africa summit is intended to strengthen ties as China ramps up its investment in the continent

US companies have pledged $14bn (£8.3bn) of investment in Africa in areas such as energy and infrastructure, US President Barack Obama has said.

The announcement came at the first US-Africa Leaders' Summit, attended by over 40 African heads of state.

The summit is an effort to strengthen US ties with Africa as China increases its African investments.

Mr Obama also hosted a dinner for African leaders at the White House.

The deals announced on Tuesday included a $5bn partnership between private-equity firm Blackstone and Aliko Dangote, Africa's richest businessman, for energy infrastructure projects in sub-Saharan Africa, as well as more investments in Mr Obama's Power Africa initiative.

According to the White House, Power Africa received an additional $12bn in pledges towards its effort to develop energy supplies on Africa through a mix of investment and state involvement.

Image copyright Getty Images Image caption President Obama toasting his guests at a White House dinner

Image copyright Getty Images Image caption Malawi's President Mr Mutharika and his wife were among Mr Obama's guests

Image copyright Getty Images Image caption Ivory Coast's Prime Minister Daniel Kablan Duncan also attended the White House dinner

'Unlocking growth'

The World Bank announced a $5bn investment in Power Africa and General Electric said it had committed $2bn to help boost infrastructure and access to energy.

"We gave it to the Europeans first and to the Chinese later, but today it's wide open for us," said General Electric chief executive Jeff Immelt.

Mr Obama also said that the US would offer an additional $7bn of financing through the Doing Business in Africa (DBIA) Campaign, bringing the total new US commitments to investment in Africa announced on Tuesday to $33bn.

"Up to tens of thousands of American jobs are supported every time we expand trade with Africa", said Mr Obama.

"As critical as all these investments are, the key to unlocking the next era of African growth is not going to be here in the US, it is going to be in Africa, " he added.

The three-day summit ends on Wednesday.