Participating civil society groups, worried about the effects of so-called blood diamonds, say Zimbabwe's human rights failings have been ignored.
The Marange fields in the east of the country have been described as the richest diamond find of the decade.
An inspection team from the Democratic Republic of Congo, the current chair of the Kimberley Process, found that Zimbabwe did meet the minimum necessary standards.
Its statement at the close of a meeting in DR Congo said Zimbabwe could start selling diamonds from there again, but insisted on continued monitoring.
Human rights groups say local people have been forced to work in the diamond fields, smuggling is rife and some mines in Marange are controlled by Zimbabwe's military, who channel some of the funds to President Robert Mugabe's Zanu-PF party.
The Zimbabwean authorities deny the charges.
"We want to be treated like any other country. I'm going to sell our diamonds now," Zimbabwean Mines Minister Obert Mpofu told the Reuters news agency.
Dissenting representatives from civil society groups walked out of the Kimberley meeting before the final statement, saying the values of the organisation were being undermined.
The new ruling is a relaxation of the Kimberley Process decision in July 2010 to allow limited diamond exports from Marange to resume.