Like-for-like sales at Boots rose by 6pc during the quarter to the of May across its retail operation, the 13th consecutive quarter of market share growth.
However, this was not enough to prevent Walgreens from slashing its profit forecast for the year which led to its share price tumbling by 25pc – its biggest one-day fall since 1980.
Last year the group announced plans to find cost savings of up to $1bn (£790m) which includes a commitment to close around 650 Boots stores in Britain.
It said 484 have already been shuttered as of February this year, leaving it with 1,900 in total.
Walgreens had first attempted to offload Boots in 2022 but abandoned its plans after suitors failed to meet its asking price of £7bn.
Mr James had previously promoted the retailer’s chances of listing in London.
Prior to joining Boots, he spent four years at the helm of Dixons Carphone, the electronics retailer now known as Currys which was a publicly listed company.
Last month the business leader dealt a major blow to Rishi Sunak by endorsing Sir Keir Starmer, despite his close connection with foreign secretary Lord Cameron and Boris Johnson.
Mr James, who is the son of the 5th Baron Northbourne, attended Eton alongside the two former prime ministers and became particularly close to Lord Cameron while both members of the Bullingdon Club at Oxford University.
In 2011 Lord Cameron is said to have holidayed with Mr James in the businessman’s £10,000-a-week luxury 15-bedroom Italian villa, although his trip was cut short as the then prime minister had to fly home to deal with the London riots.
In a pre-recorded message shared at a Labour rally event, Mr James endorsed Rachel Reeves’s plan to “put more money in people’s pockets” and praised Sir Keir for visiting a Boots store earlier in the year and pledging to “look after our high street”.