Private-equity fund HitecVision AS and Omani oil group Petrogas E&P LLC have teamed up to buy a portfolio of Total SA's British North Sea oil fields for $635 million, the companies said July 10.

The fields, which are set to produce 25,000 barrels of oil equivalent per day (boe/d) this year, will be owned by a subsidiary of the two groups called Petrogas NEO UK Ltd. which they want to expand to produce more than 100,000 boe/d within two to three years.

The British North Sea has seen a change of guard since the oil price collapsed to below $30 a barrel in 2016 with big companies selling fields to new private-equity-backed operators seeking to squeeze more barrels out of the mature basin and then exit.

HitecVision, an offshore energy-focused fund with $5.5 billion under management, last December partnered with Eni SpA to build Vår Energi AS, now one of Norway's largest producers at 169,000 boe/d. It has paid out $1 billion in dividends to HitecVision shareholders in Var.

HitecVision plans to turn Petrogas NEO—controlled equally by the two partners—into a U.K. version of Var.

"The current acquisition is the first step ... and provides a fundament for further expansion through organic and in-organic activities," Petrogas NEO's owners said in a statement.

When asked about a potential stock market listing of the new vehicle, HitecVision senior partner John Knight told Reuters there were many possible exits for a private equity firm.

These include mergers, dividend payouts and sales to financial investors, he said, adding HitecVision was looking at opportunities for consolidation within its portfolio.

Hitecvision also owns Verus Petroleum Ltd., which produces around 17,000 boe/d.

Wednesday's deal is backdated to Jan. 1 this year and expected to close in the fourth quarter, pending regulatory approval.

The oil-focused portfolio includes Total-operated fields Dumbarton, Balloch, Lochranza, Drumtochty, Flyndre, Affleck, Cawdor and minority stakes in CNOOC-operated Golden Eagle, Scott and Telford, the buyers said.

Several fields can be developed further to squeeze as many barrels as possible from the portfolio.

Total's overall production in Britain was 185,000 boe/d last year, according to its website, with gas accounting for more than half.