Google has said that it is hiring “significant numbers of people” to crack down on adverts appearing alongside extremist content, after several major corporations suspended publicity deals with the technology giant and its YouTube video platform.

In a blog post, Philipp Schindler, Google’s chief business officer, wrote that the company had started to ramp up changes around “ad policies, our enforcement of these policies and new controls for advertisers”.

“We know advertisers don’t want their ads next to content that doesn’t align with their values. So starting today, we’re taking a tougher stance on hateful, offensive and derogatory content,” he wrote.

“This includes removing ads more effectively from content that is attacking or harassing people based on their race, religion, gender or similar categories. This change will enable us to take action, where appropriate, on a larger set of ads and sites,” he added.

He said that Google would also crack down on YouTube content.

“The YouTube team is taking a hard look at our existing community guidelines to determine what content is allowed on the platform – not just what content can be monetised,” he wrote.

At the annual Advertising Week Europe event in London on Monday, Matt Brittin, Google’s president for Europe, the Middle East and Africa, apologised to companies affected by adverts appearing on extremist content.

As well as corporate giants, including Marks & Spencer and HSBC, the Government last week said that it had suspended its advertising on YouTube for appearing alongside content deemed homophobic, extremist or anti-Semitic.

Mr Schindler on Tuesday said that Google is changing the default settings for where adverts appear “so that they show on content that meets a higher level of brand safety and excludes potentially objectionable content that advertisers may prefer not to advertise against”.

Companies and brands will still be able to advertise on broader types of content if they choose to do so.

The world’s most valuable brands Show all 10 1 /10 The world’s most valuable brands The world’s most valuable brands 1st - Google Google replaced Apple as the world’s most valuable brand, with a brand value of $109.5bn, according to Brand Finance The world’s most valuable brands 2nd - Apple Apple’s brand value declined from $145.9bn to $107.1bn in 2016 The world’s most valuable brands 3rd - Amazon Amazon's brand value rose from $69.6bn to $106.4bn in 2016 Amazon The world’s most valuable brands 4th - At&t Of the 40 telecoms brands in the ranking, AT&T in 2016 overtook Verizon as the most valuable brand rising to $87bn from $59.9bn the year before The world’s most valuable brands 5th - Microsoft Microsoft's brand value rose marginally from $67.3bn to $76.3bn in 2016 The world’s most valuable brands 6th - Samsung Amazon's brand value rose from $58.6bn to $66.2bn The world’s most valuable brands 7th - Verizon Verizon's brand value inched up from $63.1bn to $65.9bn The world’s most valuable brands 8th - Walmart Walmart's brand value rose from $53.6bn to $62.5bn The world’s most valuable brands 9th - Facebook Facebook's brand value increased sharply from $34bn to just shy of $62bn The world’s most valuable brands 10th - ICBC ICBC saw its brand value rise to $47.8bn from $36.3bn. It was the most valuabe financial brand in the world in 2016 replacing Wells Fargo

He also said that Google will offer advertisers and agencies more transparency on where their adverts are running. To implement the changes, Google will be hiring “significant numbers of people”.