A buoyant Brent price has helped keep the wolves from BP‘s (LSE: BP) door.

Crude values galloped a fifth higher during April-June, the commodity even breaching the $52-per-barrel marker for the first time since November. As a consequence BP has seen its share price ascend 13% so far in Q2.

However, the broad risk-aversion sweeping financial markets more recently has seen Brent give back some of these gains, the market absorbing the possible impact of Brexit on the global economy and consequently oil demand.

I’m convinced these concerns are likely to build in the coming months as the UK political vacuum — and subsequent uncertainty over the terms and timings of Britain’s separation — drags on.

The oil price is already facing massive hurdles to growth as US drillers get back to work, and output freezes from the OPEC cartel appear as far away as ever. And these worrying supply trends are expected to persist.

Given these factors, a huge forward P/E rating of 28.6 times at BP leaves plenty of space for a retracement, in my opinion.

Digger ready to dive?

Energy and metals giant BHP Billiton (LSE: BLT) has also fared well during the second quarter, its stock value climbing 8% since the start of April.

But like BP, I reckon the poorly supply and demand indicators washing over BHP Billiton’s core markets are likely to weigh on its stock value during the coming quarter, particularly if economic data from China keeps on disappointing.

Indeed, iron ore — by far BHP Billiton’s single largest market — continued its steady collapse in recent days and was last dealing around $50 per tonne. This marks a $20 discount from levels punched just three months ago.

And BHP Billiton, like many of its industry peers, threatens to scupper a sizeable long-term uptick in material prices by increasing the amount of material it digs out of the ground. Just this week the firm announced plans to hike exploration spend around 30% in 2017, to $900m.

In light of BHP Billiton’s poorly earnings outlook, I believe a prospective P/E rating of 68.1 times is far too heady, and could lead to a hefty share price reversal in the weeks ahead.

Sales pressures persist

Shopping giant Tesco (LSE: TSCO) hasn’t performed so well during the outgoing quarter however, the stock falling 20% since the end of March.

The company advised last week that like-for-like sales in the UK rose 0.3% during March-May, the second consecutive quarterly rise for years.

Still, this marks a slowdown from the 0.9% advance Tesco enjoyed during the prior three-month period. And signs of further revenues deceleration in what the chain describes as a “challenging market with sustained deflation” could send investor sentiment sinking further.

With Tesco also dealing on an elevated P/E rating of 23 times for the current period, and its competitive pressures rising in the UK grocery market, I believe additional share price pressure can be expected.

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Royston Wild has no position in any shares mentioned. The Motley Fool UK has recommended BP. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.