Under the deal, a consortium of state-owned Chinese companies agreed to build roads, railways, hospitals and universities in return for the right to develop a copper and cobalt mine.
But pressure to alter the deal has come from western donors that will not offer relief on historic debt of $11bn to the cash-strapped government of President Joseph Kabila, if it accepts Chinese financing on commercial terms.
Congo is eager to take advantage of a debt relief scheme for poor countries and to access new forms of western development aid, but it cannot do so until the International Monetary Fund approves a new programme for the country, which it is not ready to do.