During the first six months of 2012, Paulson's Advantage Plus fund lost 18 percent, pushed lower by an 8 percent tumble in June. The portfolio's sister fund, the Advantage Fund, fell 5.7 percent in June and is now off 11.6 percent for the year.

The firm's gold fund was off slightly in June and is now down 23 percent for the year. Losses in June also took a chunk out of his better-performing funds including the Credit fund which is now up 2.2 percent for the year. The Recovery fund is up 3.5 percent for the year while the Partners fund is up 2.5 percent for the year.

Paulson, who has been one of the $2 trillion hedge fund industry's most-watched investors, broke the bad news to his wealthy clients earlier on Tuesday.

These fresh losses offer new evidence that the much hoped-for turnaround at one of Paulson's biggest portfolios is nowhere in sight. The numbers also seem to be a repeat of last year when the Advantage Plus fund was off 18 percent before going on to lose more than 50 percent for full-year 2011.

Most of the losses were driven by the fact that Paulson's very dim view on Europe proved to be wrong last month.

A spokesman for the firm declined to comment.

(Reporting by Svea Herbst-Bayliss; editing by Matthew Lewis)