Marijuana sales in Maine may be delayed after the governor vetoed a proposed law establishing a system to license, tax and track cannabis sales.

In a widely anticipated move, Republican Gov. Paul LePage rejected the bill Friday. Legalization advocates are now gearing up for a veto-override attempt. Maine’s voters last fall legalized marijuana and tasked lawmakers with developing a sales-and-monitoring system.

In his veto message, LePage said he felt the proposal conflicted with federal law, sent the wrong message to kids about drug use and that legalization could lead to increased violence and car crashes in Maine. LePage also called on the federal government to clarify how it plans to address state-level marijuana legalization.

“Until I clearly understand how the federal government intends to treat states that seek to legalize marijuana, I cannot in good conscience support any scheme in state law to implement expansion of legal marijuana in Maine,” LePage wrote. “If we are adopting a law that will legalize and establish a new industry and impose a new regulatory infrastructure that requires significant private and public investment, we need assurances that a change in policy or administration at the federal level will not nullify those investments.”

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Marijuana remains illegal at the federal level. While President Trump has said states should be allowed to make their own decisions, Attorney General Jeff Sessions has indicated the federal government may crack down.

Legalization opponents cheered LePage’s decision, calling his veto of the "reckless bill" a victory for public health. "It is clear the majority of Mainers would support an approach that puts health, safety, and families first-and not Big Marijuana,” Scott Gagnon, chairman of the group Smart Approaches to Marijuana Maine, said in a statement.

Maine lawmakers are set to vote Monday on a veto override. If lawmakers override LePage, recreational sales could begin as soon as February. LePage previously asked legislators to push back implementation to 2019.

Maine is one of eight states where voters have legalized recreational marijuana use for adults, although only a handful — Colorado, Oregon, Washington, Nevada and Alaska — have functioning marketplaces. California and Massachusetts are set to begin sales next year. While Washington, D.C. voters have legalized pot, the city cannot create a sales system until Congress agrees.

In the interim, enterprising marijuana dealers in Main have been exploiting the state's lack of regulation and enforcement by giving away cannabis but charging hefty delivery fees.