Louise White, Camelot's public affairs manager, told delegates to a Scottish conference on the lottery: "Socially there have been obvious areas of concern, particularly with regard to addiction and underage playing."
The Methodist Church welcomed the admission as "an acknowledgement of reality".
Speaking in Edinburgh, Ms White added: "The addiction problem does exist. There is undoubtedly a small percentage of players who are unfortunately spending more than they should on the lottery." Ms White agreed later at a news conference that even a tiny percentage of the playing population could mean there were many thousands of addicts.
Her comments came on the eve of today's rollover draw, which carries an estimated jackpot of pounds 20m. But the main cause for concern, she said, were the 'Instants' scratchcards.
David Deeks, co-ordinating secretary on church and social matters for the Methodists, said: "We have said from the very beginning that the introduction of 'Instants' has brought to the National Lottery a way of gambling which is known to be compulsive."
Methodists have called for the abolition of scratchcards, but short of that they want the minimum age for players to be raised from 16 to 18 and television advertising to be banned.
Leading clerics from all denominations are united over their concerns surrounding the lottery and a group representing the Council of Churches of Britain and Ireland has already met Virginia Bottomley, the Secretary of State for National Heritage, to voice their fears.
Gamblers' Anonymous would not be drawn on the controversy, but a spokesman for Oflot, the National Lottery regulator, said: "The Director General has a duty not to license any game which he considers will contribute to excessive play. He has not licensed any such game."
Seven scratchcard surveys, involving 13,000 people, had been carried out Oflot's behalf, but findings to date were "unreliable".
"The picture is becoming clearer, but what we can say is that there is no evidence of addiction in this country," said the spokesman. "Oflot has discussed the possibility of addiction with Gamblers' Anonymous and other counselling groups and asked to be advised of any information."Reuse content