The battle for the future of GP surgery owner Assura escalated yesterday after a rival urged it to reject a bid from a private equity predator.

Assura this week recommended that shareholders accept a sweetened £1.7billion bid from American buyout giant KKR and New York investment firm Stonepeak.

The deal would see properties leased to the NHS, including doctors' surgeries, hospitals and hospices, fall into the hands of overseas owners.

Most recently, Primary Health Properties (PHP) offered £1.68billion to buy Assura but it argued yesterday that its cash and stock bid is now worth more – as the value moves depending on share prices.

And PHP dismissed Assura's claim that its offer posed 'material risks and downsides' for shareholders as it urged investors to take no action in relation to KKR's bid.

A takeover by PHP would retain the properties under the ownership of a London-listed business. And it said Government spending plans for the NHS over the next three years would benefit both firms.

KKR and PHP have been locked in a months-long tussle which has seen both parties

up their offers several times since February to try to clinch a deal.

The US private equity giant has made a 'best and final' cash offer of £1.7billion, up from its previous bid of £1.61billion.

The bid of 52.1p per share includes two dividends: one which has already been paid and another that was declared last month.

Russ Mould, investment director at broker AJ Bell, said: 'Shareholders in Assura now have the luxury of sitting back to watch what happens, in the view that some sort of deal seems certain.'

Assura declined to comment.