* Lawmakers want lower stakes for betting terminals
* William Hill says lawmakers' group has little credibility
* Shares in William Hill, Ladbrokes fall 7 pct (Adds background, William Hill comment)
LONDON, Dec 8 (Reuters) - Britain should drastically reduce the amount of money gamblers can stake on fixed-odds betting terminals to tackle addiction and associated crime, a group of lawmakers said on Thursday.
The maximum stake should be reduced from 100 pounds ($127) to only 2 pounds, they said, and the government should also consider slowing the speed of spin on the machines to reduce the amount wagered in a session.
A fixed odds betting terminal is a touch screen machine found in betting shops that allows players to bet on the outcome of various games such as roulette with fixed odds.
Introduced 15 years ago, the machines have become a lucrative business for high street betting shops and helped them to survive despite the growth of online gambling.
Charities have warned that the machines are highly addictive and they can results in gamblers losing hundreds of pounds in less than a minute. Some opponents also argue that the machines can be used to launder money from criminal activities.
Shares in bookmakers William Hill and Ladbrokes Coral were trading down 7.2 percent and 6.8 percent, respectively at 1225 GMT, after the group published its interim findings. A final report will be published in January.
"The government has a duty to protect the most vulnerable in our society and to act in the public interest," said Carolyn Harris, an opposition Labour MP who is chair of the group.
"We strongly urge them to do so and do so with immediate effect."
Ministers have already launched a review of the gambling industry, including the betting terminals.
William Hill said the report had come from a small group of lawmakers who had formed their conclusions before they had begun investigating the issue.
"They are not a Select Committee (an official committee of lawmakers) and have little credibility in terms of independence," it said.
Analyst Roberta Ciaccia at Berenberg said it was not the first time that politicians had proposed the 2 pounds per spin maximum stake, and she continued to believe it was an "extremely unlikely scenario".
She said the average stake per session was 10 to 15 pounds. Setting a limit below that level would wipe out the vast majority of betting shops, put 50,000 jobs at risk and reduce government tax receipts from bookmakers, she said. ($1 = 0.7885 pounds) (Reporting by Paul Sandle; editing by Kate Holton/Keith Weir)