Beijing, China ? China launched a sweeping effort Saturday to expand its access to Africa’s oil and markets, pledging billions of dollars in aid and loans as dozens of leaders from the world’s poorest continent opened a conference aimed at building economic ties.

African leaders at the two-day meeting said they welcomed Chinese investment and business ties, but Beijing also faces criticism that it is treating Africa like a colonial territory and supports regimes with poor human rights records.

President Hu Jintao pledged to double China’s aid to Africa from its 2006 level by 2009. Speaking at the conference’s opening ceremony, he promised $3 billion in loans, $2 billion in export credits and a $5 billion fund to encourage Chinese investment in Africa.

The two-day event includes heads of state from 35 of the 53 African nations and top officials from 13 others – one of the largest such gatherings in history.