By Jason McLure

LITTLETON, N.H., June 21 (Reuters) - New Hampshire's Democratic governor on Thursday vetoed a bill passed by the Republican-controlled legislature that would legalize medical marijuana in the state, bucking a trend towards legalization in New England.

Governor John Lynch said the measure did not provide sufficient restrictions on the cultivation and prescription of marijuana. He also opposes provisions authorizing teenagers to use it for treatment.

"I cannot support establishing a system for the use of medical marijuana that poses risks to the patient, lacks adequate oversight and funding, and risks the proliferation of a serious drug," Lynch said.

For the moment, Lynch's move halts the spread of medical marijuana dispensaries in New England.

Maine, Rhode Island, Connecticut and Vermont have all legalized pot for medical use in recent years. Massachusetts voters will decide whether to legalize use in a ballot measure in November.

Nineteen states have passed laws allowing marijuana use for medical purposes.

"The legalization efforts in New England have really been the area that is the most active in recent years," said Keith Stroup, legal counsel at the National Organization for the Reform of Marijuana Laws.

The New Hampshire bill passed by a more than 2 to 1 margin in the state House of Representatives this year, but only narrowly passed the Senate, making prospects for a veto override unlikely. (Editing by Barbara Goldberg and Xavier Briand)

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  • Alaska

    Legalized for medical use. <a href="http://www.flickr.com/photos/alanasise/6847095796/" target="_hplink">Flickr: alana sise</a>

  • Arizona

    Legalized for medical use. <a href="http://www.flickr.com/photos/billward/110338154/" target="_hplink">Flickr: Bill Ward's Brickpile</a>

  • California

    Legalized for medical use. <a href="http://www.flickr.com/photos/gerbache/2260207829/" target="_hplink">Flickr: gerbache</a>

  • Colorado

    Also legalized possession by non-medical users. <a href="http://www.flickr.com/photos/dok1/520845832/" target="_hplink">Flickr: dok1</a>

  • Connecticut

    Legalized for medical use.

  • District Of Columbia

    Legalized for medical use. <a href="http://www.flickr.com/photos/bigberto/2770838680/" target="_hplink">Flickr: ~MVI~ (off to coron)</a>

  • Delaware

    Legalized for medical use. Flickr: <a href="http://www.flickr.com/photos/dougtone/7749689644/">Doug Kerr</a>

  • Hawaii

    Legalized for medical use. <a href="http://www.flickr.com/photos/ricardo_mangual/6006230817/" target="_hplink">Flickr: Ricymar Fine Art Photography</a>

  • Maine

    Legalized for medical use. <a href="www.flickr.com/photos/indywriter/2683524563/" target="_hplink">Flickr: indywriter</a>

  • Massachusetts

    Passed ballot initiative for legalized medical marijuana in 2012.

  • Michigan

    Legalized for medical use. <a href="http://www.flickr.com/photos/kayoticblue/213316452/" target="_hplink">Flickr: ckay</a>

  • Montana

    Legalized for medical use. <a href="http://www.flickr.com/photos/csbarnhill/2633187564/" target="_hplink">Flickr: csbarnhill</a>

  • Nevada

    Legalized for medical use. <a href="http://www.flickr.com/photos/http2007/4699361533/" target="_hplink">Flickr: http2007</a>

  • New Jersey

    Legalized for medical use. <a href="http://www.flickr.com/photos/paulflannery/4021996652/" target="_hplink">Flickr: psflannery</a>

  • New Mexico

    Legalized for medical use. <a href="http://www.flickr.com/photos/everyskyline/3134662783/" target="_hplink">Flickr: michaelwhitney</a>

  • Oregon

    Legalized for medical use. <a href="http://www.flickr.com/photos/d-powell/2099638403/" target="_hplink">Flickr: digging90650</a>

  • Rhode Island

    Legalized for medical use. Also decriminalized possession of less than one ounce.

  • Vermont

    Legalized for medical use. <a href="http://www.flickr.com/photos/bryanalexander/6129117/" target="_hplink">Flickr: BryanAlexander</a>

  • Washington

    Legalized for medical use. Also legalized possession by non-medical users. <a href="http://www.flickr.com/photos/rose_braverman/6924724331/sizes/l/in/photostream/" target="_hplink">Flickr: Rose Braverman</a>

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