A few Flickr users have become disgruntled since an announcement by the website that all Old Skool users, those who had Flickr accounts before the company was bought by Yahoo, would have to open a Yahoo account and use a Yahoo username to sign into the photo sharing site.

Flickr has promised that once the accounts are merged, you just have to sign into Flickr once, and then will remain logged in.

Yahoo has said that the older email-based Flickr sign-in system would end 15 March, when everyone will be required to have a Yahoo ID to sign into their account.

However, nothing else so far will change, and there are no plans to make people switch over to Yahoo Photos instead.

The Old Skool Flickr users seem to be objecting that they're being treated as “second class citizens”, despite being the site's oldest users.

A number of them have posted to the Flickr forum, saying, for example, “I don't like yahoo and I don't like my Yahoo account".

“I take pride in being an old skool member”, said Flickr user Joe Philipson.

Yahoo has released a statement that says, in part, “We are simplifying the registration process, and we continue to focus on innovation, ease of use, and new functionality".

"At this point, the vast majority of Flickr users already have Yahoo IDs, and this will not a affect a significant number of users.”