LONDON (Reuters) - The campaign for Britain to leave the European Union holds a one-point lead over the "In" camp ahead of Thursday's membership referendum, according to a survey published by polling firm Opinium on Wednesday.
Opinium said the campaigns were effectively running neck and neck as the online poll put support for "Leave" at 45 percent and "Remain" at 44 percent, with the remaining 9 percent of respondents still undecided.
Sterling fell against the dollar and the euro on news of the poll while demand rose for safe-haven government bonds.
"This puts the two campaigns in a statistical dead heat with each side being within the margin of error of the other despite a larger than usual sample," Opinium said on its website.
The poll was based on 3,011 interviews conducted between June 20 and 22.
Opinium's previous poll, published on Saturday, had put the two camps level at 44 percent, based on polling between June 14 and 17.
Three other opinion polls were expected to be published later on Wednesday.