Virginia on Wednesday became the first southern US state to approve the use of small amounts of marijuana for personal use.

The state Senate and House of Delegates voted to allow adults to possess marijuana as of July 1, in a measure approved despite fierce opposition by Republican lawmakers.

Democratic Governor Ralph Northam in a statement said his state had "made history as the first state in the South to legalize the simple possession of marijuana."

"Marijuana laws were explicitly designed to target communities of color, and Black Virginians are disproportionately likely to be stopped, charged, and convicted," he said.

"Today, Virginia took a critical step to right these wrongs and restore justice to those harmed by decades of over-criminalization."

Several other US states, including New York and Colorado, have legalized marijuana, but Virginia is the first to do so in the socially conservative US south
Several other US states, including New York and Colorado, have legalized marijuana, but Virginia is the first to do so in the socially conservative US south GETTY IMAGES NORTH AMERICA / BRUCE BENNETT

Several other US states, including New York and Colorado, have approved similar measures, but Virginia is the first to do so in the socially and politically conservative US south.

A measure approved by the state in February would have seen the state legalize pot by 2024, but Northam asked lawmakers to move that date forward in a bid to keep regular users out of trouble.

Adults over the age of 21 will be able to legally possess up to one ounce (28.3 grams) of cannabis for personal use, as well as cultivate up to four plants per household.

Like limits on drinking in public, consuming cannabis in public will not be allowed.

The licensing of cannabis production and commercial cannabis sales will not take place until July 1, 2024.

"Legalization will bring an end to the thousands of low-level marijuana infractions occurring annually... ending a discriminatory practice that far too often targets Virginians who are young, poor, and people of color," said Jenn Michelle Pedini with NORML, a national group lobbying for pot legalization.