Feb. 21 (UPI) -- The Dutch lower house of parliament on Tuesday barely passed a bill to decriminalize cultivation of marijuana in the Netherlands, but its slim approval might signal that the proposal is in for a steeper hill to climb in the senate.

Marijuana is available in licensed Dutch "coffeeshops" for personal use but the actual production of the plant to supply those shops is illegal. As a result, retailers must open themselves to potential prosecution by growing their own pot or buying it from criminal networks.

On Tuesday, the lower house, the Second Chamber, voted largely along party lines in narrowly approving the proposal. Submitted by lawmaker Vera Bergkamp, a member of the liberal D66 party, the measure passed by just five votes, 77-72.

"One of my main motivations is to reduce as much as possible the risks to public health by regulating the cultivation can impose requirements on the production and hence on the quality," Bergkamp said. "Another important point is that we achieve the cultivation [for] coffee shops ... and thus remove trade for organized crime.

"This is an important step to end a stalemate that has lasted far too long."

Contrary to popular belief, marijuana is a controlled substance in the Netherlands -- but small-scale distribution by licensed shops has been condoned since the mid 1970s. The Dutch Ministry of Justice has a policy of tolerance for so-called "soft drugs," which covers cannabis, up to five grams. Large-scale dealing, cultivation, import and export, however, are heavily investigated and prosecuted by authorities.

The justice ministry's tolerance policy also allows cultivation of up to five marijuana plants. Supporters of the bill, however, argue that the government's legal view of marijuana cultivation directly conflicts with its tolerance for sales.

Tuesday's legislation, though, is thought to be unlikely to be passed by the senate, or First Chamber, BBC News reported. Prime Minister Mark Rutte opposes the measure.

Bergkamp said decriminalizing pot cultivation will wipe away the disconnect between the production and sale of marijuana, and make it safer for shops to acquire supplies of the drug.

If the legislation passes, marijuana production would be monitored and regulated -- and possibly taxed -- by the Dutch government.