Lord McAlpine last night said people who tweeted or retweeted allegations wrongly linking him to child abuse would have to pay different levels of compensation, depending on how many followers they have on the social networking site.

The Tory peer, who had no involvement in the sex abuse scandal, despite a botched BBC Newsnight investigation into allegations surrounding a North Wales children's home, said those with less than 500 should pay a "modest" sum of compensation to Children In Need.

A statement said: "Given the large amount of information that continues to be disseminated, the band for what the charity payment shall be, will be settled when Lord McAlpine has a full understanding of this material.

"The donation is intended for tweeters with fewer than 500 followers, but those with larger numbers of followers are still encouraged to identify themselves and offer their formal apologies at this stage."