Premier Investments has extended its offer for Just Group by over a month to 15 August, but the Australian retailer's board is showing few signs of considering the bid.

Premier, chaired by retail mogul Solomon Lew, first tabled its AUD814m (US$777m) offer for the clothing retailer in May.

But Just Group's board has once again reacted unfavourably to the offer, saying Premier wants to "get the company on the cheap."

Just Group chairman Dr Ian Pollard went onto say: "The offer is opportunistic and fails to reflect the long term value of Just Group."

Earlier this month, Just Group dropped its full-year forecast to be between 29.2 and 30.6 cents per share, compared to 33.4 cents as included in its recent target's statement.

In reaction, Premier released a statement saying it was "concerned and astonished" by the profit downgrade.

Lew said at the time: "Premier has no confidence in anything that the Just board says about its future performance and we are currently considering our position in relation to our bid."