COLUMN - (John Kemp is a Reuters market analyst. The views expressed are his own)

By John Kemp

LONDON, March 18 (Reuters) -

Hedge fund managers have become more cautious about buying oil since the end of February as doubts about the global economy resurface, dampening expected price rises from OPEC-led production cuts and U.S. sanctions on Iran and Venezuela.

Front-month Brent futures prices were steady in the last week of February and the first part of March, giving funds little incentive to continue buying in the short term.

Although hedge funds and other money managers were net buyers of 5 million barrels of Brent crude futures and options in the week to March 12, that mostly only reversed the 4 million barrels of net sales seen the previous week.

That left portfolio managers' net long position essentially unchanged from Feb. 26 at 293 million barrels, after an increase of 155 million barrels over the previous 12 weeks since Dec. 4 (https://tmsnrt.rs/2ULwvU0).

Fund managers now hold almost six bullish long positions for every bearish short one, up from a ratio of just 2:1 in early December but still modest compared with the ratio of 19:1 before oil prices started to slide in early October.

The same caution has spread to fund buying of refined fuels such as distillates as financial investors temper their previous optimism.

Fund managers have been net buyers of European gasoil futures and options for ten weeks running, boosting their total position by 74 million barrels since the start of the year.

But a net purchase of 2 million barrels in the week to March 12, according to positions records from ICE Futures Europe, is the smallest increase so far in the current buying cycle.

Until some of the uncertainty surrounding the outlook for the economy and resulting oil demand is resolved, oil prices and hedge fund positions are likely to remain in a holding pattern.