Microsoft has accused Google of spamming users following the company’s introduction of revamped Gmail services in May this year.

Google revamped its Gmail services by introducing a ‘simpler design’ and organisational tools that allow users to improve control over the content within their inboxes.

The search engine firm has introduced new inbox groups for users’ mails including categories such as primary, social, promotions and updates, which appear as different tabs.

Microsoft said that Google violates users’ privacy by reading every single word of every single email sent to and from Gmail accounts so they can better target ads.

"Now, they’re going one step further over the line by using that same personal information to spam your inbox with ads that look like real emails," a Microsoft spokesperson said.

"Your email provider should protect you from spam, but Google is doing just the opposite; they’re reading your private email conversations and using what they find to push junk mail directly to your Gmail inbox.

"We don’t scan the content of your email to target you with ads, and don’t spam your inbox with ads that look like personal email."