Harworth has doubled down on its rejection of Peel’s £583M takeover bid, a day after Peel criticised how the company is being run.

Harworth Group’s board remains “unanimous and unequivocal” in its opposition to Peel’s 172.5p-a-share cash offer, arguing that the bid fundamentally undervalues the business and the development pipeline it has built across northern England and the Midlands.

The Rotherham-based regeneration and strategic land specialist said it would publish its full response by 9 September after reviewing Peel’s offer document with advisers.

“In particular, shareholders are advised not to sign or return any form of acceptance and not to submit any electronic acceptance in respect of their Harworth shares,” Harworth Group said in a statement.

The latest move comes after Peel published its offer document on Wednesday, escalating a takeover battle that began earlier in the month.

Peel, through its wholly owned subsidiary Peel Pepper, is offering 172.5p in cash for each Harworth share, valuing the entire company at approximately £583M. Peel already owns nearly 30% of Harworth through Goodweather Holdings. The offer will remain open until 25 October.

The bid represents a 20% premium to Harworth’s 144p closing share price on 5 August, the day before the offer period began, and a 36% premium over its three-month volume-weighted average price.

Harworth shares are trading at about 178p, implying the market thinks Peel might have to increase its bid to buy the company.

In its offer document, Peel argued that Harworth’s public listing and strategy have failed to generate adequate returns, highlighting rising administrative and financing costs. It said Harworth’s annualised total accounting return over the relevant period was only 4%, while administrative expenses and finance costs had risen substantially.

Peel also said Harworth’s cash flow profile was becoming “increasingly less sustainable” and said there is not as much potential upside in its development pipeline as the company believes.

Harworth’s board has argued from the outset that the bid exploits a disconnect between its share price and the underlying value of its assets and development pipeline.

“Harworth’s board remains confident in Harworth’s ability to deliver attractive long-term returns for shareholders,” Harworth Group said in its earlier response to the offer, pointing to an average 8% total accounting return over the past five years.

The company holds more than 15,000 acres with development potential for over 35M SF of workspace and around 29,000 homes, plus data centres, the company said. It has signed a deal with Microsoft at Skelton Grange in Leeds, and at the start of August, it said it was in advanced talks to sell another site with hyperscale data centre potential.

In its 7 August response to Peel, the company said it was accelerating the reallocation of capital toward higher-returning opportunities in powered land and industrial growth sectors.