Myer says it still has the support of its banks and has not breached debt covenants after warning first-half profit will fall as much as 41 per cent, triggering claims by Solomon Lew's Premier Investments that the retailer is in "peril".

In its third profit warning since July, Myer said on Friday it expected underlying interim net profit to fall to between $37 million and $41 million before restructuring costs and writedowns, compared to $62.8 million in the first half of 2017. It doesn't expect trading to improve in the second half.