Hedge fund manager Crispin Odey has built up a short position against UK government debt that is now worth 154.8% of his flagship €173m European fund.
According to documents seen by the Financial Times, the position is now the single largest position on the fund.
Odey, who has publicly backed Brexit, has been building the position in 30-year debt since November 2016, five months after the vote.
Should there be a significant decline in UK government bond prices the fund is set to benefit after a difficult period for performance - the fund has dropped in size from €2.5bn at the start of 2015 to €173m.
The derivative contract is tied, which is tied to long-dated gilts that are more sensitive to rises in interest rates and inflation, is set to expire in June.
The firm declined to comment the FT on the trade.
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