The British convenience retailer also said Chief Financial Officer Simon Fuller was leaving the company.

The company now expects 2018 full-year adjusted core earnings to be at a similar level to the prior year after a 2.7 percent drop in first-half like-for-like sales.

"During the first half we experienced unprecedented supply chain disruption following the collapse of P&H last November," Chief Executive Officer Jonathan Miller said in a statement.

"This temporary upheaval has inevitably impacted sales and margin performance in the about 700 stores that were formerly supplied by P&H, and has also had knock-on effects on the rest of the estate."

McColl's, which trades from about 1,600 convenience stores and newsagents in Britain, had put in place contingency arrangements, entering into a new short-term supply contract with Nisa in early December.

McColl's also began a new supply partnership with Morrisons, Britain's No. 4 supermarket group, earlier than previously scheduled to supply affected stores with tobacco.

The switch to Morrisons supply in the 1,300 stores has been accelerated and will now be completed in early August, ahead of schedule, the company said on Monday.

Sales performance improved in the second half as supply chain disruptions slowed and as weather conditions brightened.

Like-for-like sales fell 0.8 percent in the seven weeks to July 15.

Total revenue, however, rose 19.2 percent to 601.7 million pounds ($790.5 million) for the 26 weeks ended May 27, as it bought about 300 convenience stores in 2017.

McColl's said it would begin a process to identify a new CFO and Fuller would remain until the appointment of a successor. Fuller is set to take over as finance head of Daily Mirror publisher Reach plc.

(Reporting by Arathy S Nair in Bengaluru; Editing by Saumyadeb Chakrabarty, Amrutha Gayathri)