PLEXUS Holdings, the oil and gas well engineering firm, has won $5 million (£3.5m) investment from a Russian manufacturer LLC Gusar, which provides a vote of confidence as the firm grapples with the downturn in its core North Sea market.

The Aberdeen-based firm revealed last month that it had cut workforce numbers by around 50 per cent in response to the downturn in the North Sea industry triggered by the plunge in the crude price since 2014.

This has prompted many Scots oil services firms to target growth in other markets where activity has held up more strongly than in the UK.

Plexus reckons the agreement with Gusar will help fast track the company’s entry into the Russian market, which it believes offers better growth prospects than the North Sea. The company noted reports that the oil and gas sector in Russia is benefiting from increasing levels of capital investment and activity.

Chief executive Ben van Bilderbeek said: “We are pleased to have secured additional funding for Plexus at a time when trading conditions are clearly challenging, and welcome Gusar as a new shareholder.”

The agreement comes three months after Plexus agreed a licensing deal with LLC Gusar and another Russian manufacturer, CJSC Konar. This suggests the company’s belief in the potential for its technology to win a following in Russia is shared by local players.

The deal provides fresh evidence of overseas interest in oil and gas technology developed in Scotland and tested in the waters of the North Sea.

In July last year Chinese giant Jereh International invested £8m in acquiring a stake in Plexus.

However, the two deals reflect a big drop in the stock market worth of Aim-listed Plexus in recent months.

Plexus had a stock market value of around £190m the day the Jereh deal was announced.

The deal with LLC Gusar values Plexus at around £52m.

LLC Gusar has paid 52.05p per share to acquire a 7 per cent interest in the enlarged share capital of Plexus Holdings through a placing.

Shares in Plexus Holdings closed up 7 per cent, 4.12p, at 63.62p.

Plexus said it would use the proceeds of the placing to help develop and market products for Russia and other territories and for general working capital requirements.

The company saw revenues in the UK North Sea fell by 85 per cent annually in the six months to 31 March, to £0.88m. Group revenues fell around 50 per cent, to £6.7m.

It lost £3.5m in the period.

The company told investors in March that it had shed 69 posts in recent months, leaving it with a staff of around 84 in Aberdeen.