The bank is currently negotiating the size of the fine with the Financial Conduct Authority (FCA), according to a Sky News report.
Barclays could face a £50m penalty for issues surrounding the £11.8bn capital-raisings from Qatari and other sovereign investors in 2008, which allowed the bank to escape a government bail-out.
Barclays allegedly breached listing rules by not disclosing enough details to the stock market about the deal.
However, a final agreement with the regulator is still being thrashed out and the size and nature of the penalties facing Barclays could still vary, the report said.
Barclays had been trying to get the enforcement action resolved ahead of the publication of a preliminary prospectus for its £5.8bn rights issue, designed to shore up its capital position.
Barclays’ mounting regulatory fines of recent years already include a £291m fine for its role in the manipulation of LIBOR and a contested $453m fine for rigging US energy markets.
The bank has also set aside billions of pounds to compensate customers who were mis-sold payment protection insurance and interest rate swaps.
The FCA provided its preliminary findings against Barclays on 27 June 2013 and Barclays responded on 25 July 2013 contesting the allegations.
Among those investigated are four current and former senior employees, including Chris Lucas, former group finance director, and John Varley, the bank’s former chief executive, as well as Barclays.
Among the investment bankers helping Barclays to raise the money is James Leigh-Pemberton of Credit Suisse, who was on Monday confirmed as the new head of UK Financial Investments, the body which manages taxpayers’ stakes in Britain’s bailed-out banks.
