The fast-growing photo sharing service Instagram has disabled a key feature integrating its service with Twitter.
The Facebook-owned company, famed for its sepia-toned filters and addictive sharing features, will no longer let its images be viewed directly via Twitter.
By disabling its Twitter Cards integration, users will now have to visit Instragram's website or use its app to view photos properly.
It is widely seen as a move to cement its rapid growth, which has seen it surpass Twitter in mobile users in the US - 7.3 million to 6.9 million per month.
Kevin Systrom, Instagram's founder and CEO, told the LeWeb 12 conference in Paris that the decision was just "an evolution of where we want links to our content to go".
Systrom said that since the company was acquired by Facebook, it is thought for around $1 billion, it has been able to upgrade its web presence and now wants customers to go direct for their vintage-toned photos.
"We revamped our web properties, and now we're able to staff up teams to work on web properties with the Facebook acquisition," he said. "Obviously things change as a company evolves."
Meanwhile Instagram has not disabled similar features which integrate its images into Facebook, Tumblr and Foursquare.
For its part Twitter is continuing to push its own photo-uploading solution, and is expected to introduce picture filters and editing shortly to further compete with Instagram.
Twitter said:
"Users are experiencing issues with viewing Instagram photos on Twitter. Issues include cropped images. This is due to Instagram disabling its Twitter cards integration, and as a result, photos are being displayed using a pre-cards experience. So, when users click on Tweets with an Instagram link, photos appear cropped."