The board of the UK property portal said the latest approach by REA Group “remains unattractive and continues to materially undervalue Rightmove and its future prospects,” in a stock market statement today.

The move comes after REA up its bid from £6.1bn to £6.2bn on Friday and Rightmove shareholder AXA Investment Managers said the UK board should hold “serious” talks with the Australian business.

Richmond-based REA, which is held by News Corp, has now offered the Rightmove board a bid worth 781p for the firm’s shares, valuing the business at £6.2bn.

REA says this is an 11% increase on its second bid for Rightmove on 5 September and a 41% premium on the UK firm’s undisturbed share price on 30 August, the day before the Australian firm’s interest became public.

Rightmove shareholders would hold around 20% of the enlarged business, REA said in a stock market statement.

Rightmove’s statement stressed that its chair Andrew Fisher has met with REA chair Hamish McLennan followed by a meeting of the executives of the two firms.

“No information was presented in either meeting which was materially new or different to the information which has been previously presented publicly by REA,” it said.

Rightmove added that during its discussions REA asked it to extend the 28-day ‘put up or shut up’ deadline, which ends at 5pm today, and allow the Australian firm asses to its books to carry out due diligence for a potential fifth proposal.

The UK firm said: “The board has declined requests from REA to grant due diligence access as none of REA’s proposals received to date has been at a sufficient level to grant such access.”

Its board urged shareholders to take no action over the bid, adding that “shareholder interests would be better served through the execution of Rightmove’s standalone strategic plan”.

Rightmove chairman Andrew Fisher adds: “The last few weeks have been very disruptive, as well as unsettling for our colleagues.

“To the extent REA wants to put forward a further proposal, I urge them to submit a best and final proposal ahead of today’s 5pm ‘put up or shut up’ deadline such that we can bring certainty to this process.”

AJ Bell investment director Russ Mould points out: “We’re into the final stretch in the race to buy Rightmove. REA has until 5pm today to make a formal offer, and it’s going to have to radically change the price and structure of the deal if it has any chance of winning over Rightmove’s board.

“Given that four proposals have been rejected, one would have thought REA had got the message by now that Rightmove shareholders want a whole lot more money.

“Normally by this point in the proceedings the suitor would accept defeat and retreat with its tail between its legs. Yet REA has shown a dogged determination to secure the prize so you cannot rule out one final attempt before the clock strikes five.”