Sky News has learnt that the boards of the two companies and their advisers are discussing a price of more than £30-a-share for Schneider to acquire the roughly-40% of Aveva it does not already own.

Banking sources said on Monday that a deal was expected to be struck ahead of a 21 September deadline imposed by the UK takeover watchdog.

At just over £30-a-share, the deal is expected to cost Schneider in the region of £3.5bn.

Given the French company's existing control of Cambridge-based Aveva through its 60% holding, a full buyout is unlikely to elicit significant criticism about the perceived erosion of Britain's technology base.

In recent weeks, a flurry of takeover bids from overseas companies and private equity firms has emerged for London-listed technology businesses such as GB Group and MicroFocus.

Aveva is also said by industry executives to be negotiating a series of undertakings relating to its brand and future investment under Schneider's full ownership.

Shares in Aveva closed on Monday at £29.59, giving the company a market capitalisation of more than £8.8bn.

Investment bankers at Citi are advising Schneider on the deal, while Lazard is advising Aveva.

Aveva declined to comment.