The Guardian has confirmed that it is no longer working with Facebook on Instant Articles, nor is it distributing its content through Apple News, according to a report by Digiday. However, the British daily is still said to be working with Google to publish articles using the company’s Accelerated Mobile Pages or AMP standard.

“We have run extensive trials on Facebook Instant Articles and Apple News to assess how they fit with our editorial and commercial objectives,” a Guardian spokesman said. “Having evaluated these trials, we have decided to stop publishing in those formats on both platforms.”

The British newspaper company, which has been trying to build up its financial resources with a membership drive, went on to say that its primary objective “is to bring audiences to the trusted environment of the Guardian to support building deeper relationships with our readers, and growing membership and contributions to fund our world-class journalism.”

Facebook launched Instant Articles in 2015, and offered it to publishers as a way to make their content more mobile-friendly. Under the deal, Facebook modified the stories to make them load more quickly on smartphones, and offered publishers a share of advertising revenue.

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Initially, there was a large amount of interest in the Facebook deal because many companies didn’t have their own fast-loading mobile pages or apps. Major publishers such as the New York Times and the Washington Post agreed to be part of the Instant Articles project, and some—including the Guardian—published everything they had through the feature.

Over the past few months, however, there have been rumblings of dissatisfaction among many publishers, including the New York Times, which no longer distributes its content through Instant Articles. Many media companies say the amount of revenue they’ve been getting from the Facebook feature has been lackluster.

Facebook has admitted that it needs to do more work on revenue-sharing options for publishers and media companies, and it is also introducing support for subscriptions and pay models, something more and more publishers and news sites are relying on for income.

The Guardian was also an early adopter of another Facebook venture known as “social reader apps,” which Facebook promoted in 2012. The apps allowed users to sign up for and read news content inside special apps that lived on the social network, but the Guardian pulled out of the deal after Facebook changed the way its algorithm worked and stopped recommending the apps.

While Facebook’s Instant Articles has proven to be less than stellar as a method of generating revenue, some publishers have been more complimentary about the returns they are getting from Apple News, which distributes content from partners through a news-reading app. But The Guardian said it is no longer participating in the Apple project either.

The British publisher has continued working with Google’s AMP standard, however, which like Instant Articles makes it easy for stories and other content to be viewed on mobile devices.

AMP supports subscriptions and pay models, and it is also an open-source project, which means any developer or publisher can contribute to the development of the standard. The Guardian said at a recent conference that more than 60% of its mobile traffic comes from content that it distributes through the Google project.