Candover Partners, a UK-based buyout firm, has successfully tapped the debt markets to raise its takeover offer for oil services company Expro International Group in an unusual move that will see it scale up the level of debt used on the deal just as most deals are struggling to get sufficent finance.

Last month, Candover increased its offer to £15.50 per share from £14.35 per share to beat an indicative offer from US trade rival Halliburton.