One of Britain’s largest advertising agencies has issued a warning over spending from US tech companies hours after Apple revealed a slowdown in revenues for the third straight quarter.

WPP cut its full year guidance as it said companies were delaying spending on technology projects.

It comes after Apple reported disappointing third-quarter sales of the iPhone, its flagship product, overshadowing growing services sales at the world’s most valuable company.

The world’s largest company revealed revenues of $81.8bn over the quarter, down 1pc on the previous year. Shares in Apple were roughly flat in after market trading. 

WPP said its North American business declined by 1.2pc in the first half reflecting the lower revenues from technology clients.

It cut its revenue guidance for the full year, saying growth excluding pass-through costs will be 1.5pc to 3pc, having previously guided for 3pc to 5pc.

Advertising results have been a mixed bag so far this year as rising interest rates and high inflation blunt advertising spending and delay projects. 

Chief executive Mark Read said: “Our performance in the first half has been resilient with Q2 growth accelerating in all regions except the USA, which was impacted in the second quarter by lower spending from technology clients and some delays in technology-related projects.”

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