As the oil price glut persists, big energy companies are looking to gobble up the smaller, struggling firms. Above, a worker walks past a pump jack on an oil field owned by Bashneft company in Russia, Jan. 28, 2015. REUTERS/Sergei Karpukhin

With oil prices hovering around $35 a barrel, a flurry of dealmaking could be coming soon. At least, that’s what happened two decades ago, when energy companies responded to similarly depressed prices by going on a spree of mergers and acquisitions. Pressure for a comparable industry shake-up is building now.

The oil sector is struggling worldwide, responding to low prices by laying off hundreds of thousands of workers. But the current landscape is especially bleak for the smaller firms, which find it increasingly difficult to compete. That weakness leaves them prone to be gobbled up by the larger companies, analysts say — name-brands like ExxonMobil, Chevron and Royal Dutch Shell.

“We think they’re all going to do a big deal,” energy analyst Doug Terreson of Evercore ISI told CNBC earlier this month. “We think when you consider that [exploration and production] reserves are trading at about half the level they can find reserves for with the drill bit, there are great opportunities for these companies.”

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Despite the seemingly conducive market conditions, however, industry dealmakers are staying cautious: In fact, as a report from PricewaterhouseCoopers highlighted last month, the number and volume of mergers and acquisitions in the U.S. oil and gas industry just sank to their lowest levels of fourth quarter activity in the last five years.

That’s because a handful of obstacles still loom, industry analysts and observers recently told the Financial Times.

For one, prices are still volatile. And as they continue to fluctuate, it’s challenging for investors to agree on valuations, they said. What’s more: Company share prices don’t necessarily reflect today’s low oil prices. Greg Weinberger, co-head of global mergers and acquisitions at Credit Suisse, told FT the biggest barrier to deals stems from oil companies trading as if prices were higher. On top of that, the number of struggling companies trying to unload assets and raise money may be giving some investors jitters.

Vance Scott, an analyst with Ernst & Young LLP’s Transaction Advisory Services, recently told the Wall Street Journal it’s a matter of time before mergers and acquisitions take off.

“Price distress will eventually force M&A activity,” he said.