The London Stock Exchange is to buy a 60 per cent stake in European clearing house LCH Clearnet.
The LSE will pay a lower price for the stake, €366m (£300m), about €100m below the original offer price.
According to the BBC, the lower price reflected new European rules requiring clearing houses to hold more capital, the companies said.
The report says that the deal was originally due to be completed by the end of this year. The UK’s Office of Fair Trading approved the acquisition earlier this month.