John Lewis has reported a loss for the first half of the year as a result of "difficult" trading conditions and "subdued consumer confidence".
The retailer, which also owns Waitrose, posted a £25 million loss in the first six months of its financial year, compared with a £800,000 profit in the same period last year.
It warned that a no-deal Brexit would have an increased significant impact on its business. John Lewis said it has made preparations for a no-deal, but insisted it wouldn't be able to fully absorb the affects.
The partnership's chairman, Charlie Mayfield, said: "Should the UK leave the EU without a deal, we expect the effect to be significant and it will not be possible to mitigate that impact.
"Brexit continues to weigh on consumer sentiment at a crucial time for the sector as we enter the peak trading period."
Elsewhere, salary increases and a new IT system also ate into profits, while Waitrose sales fell slightly to £3.4 billion.