Pierre Andurand, who runs one of the biggest hedge funds specializing in oil, liquidated the fund's last long positions in oil last week and is running a very reduced risk at the moment, a market source familiar with the development said.

The fund, Andurand Capital, is a renowned oil price bull but has been reducing its bullish positions gradually over the course of 2017, the source said.

The $1.5 billion fund lost 11.6 percent in the first quarter of the year, according to data from HSBC.

The losses were incurred even as oil prices remained relatively steady during January-February, which also saw record low volatility levels, undercutting many hedge funds.

However, in March and April oil prices began a steep slide as the market lost confidence in the ability of oil producing countries to quickly eradicate a market glut with output cuts.

Oil prices are now down 17 percent year-to-date but the source said Andurand Capital did not switch its long positions into shorts as it remained "fundamentally bullish on oil."

Andurand, who shot to fame in 2008 by correctly predicting the spike and subsequent fall in the oil price from a record $147 a barrel, forecast late last year that Brent would trade around $60 a barrel by the end of 2016 and rise towards $70 by this summer.

On Friday, Brent edged up from its five-month lows to trade near $49 per barrel.

In late 2015, Andurand correctly forecast the oil price would trade close to $25 in the first quarter of 2016. Brent hit a low of $27 a barrel in January that year.