Pop band One Direction have teased fans with what they promise will be ‘their biggest announcement’ ever.

Niall Horan broke the news on his Twitter page on May 9, tweeting: “THE most exciting 1D news EVER is being announced in 6 days!”.

At the end of the tweet the singer posted the link to a website which appears to have been made specifically for the news.

The website http://www.onebigannouncement.com features a countdown to May 16 when the big announcement will be revealed.

Liam Payne added to the excitement by tweeting on his personal account: “Exciting announcement coming from us nextttttt week!”

Shortly after Niall Horan’s Tweet, the website crashed as fans all rushed to the website to try and find out more information about the teaser.

The message has since been retweeted a massive 61, 522 times.

Little has been revealed about the news, with the band saying nothing further about what fans can expect on May 16.

The news has sent fans into a frenzy with many taking to Twitter to voice their guesses as to what the big news could be, with many speculating it could be something related to a new album or tour.

2013 is already shaping up to be another big year for the pop band who are currently on their sold out world tour.

They have also been filming their first movie, This Is Us, which will be released in 3D. The move is directed by Super Size Me filmmaker Morgan Spurlock.

It is also believed the band will be releasing their third studio album in Autumn of this year.

Since coming third in the X Factor in 2010 the band have achieved enormous success around the world; making them one of the most successful acts to come from a talent show.

One thing is for sure, there will be a few sleepless nights for One Direction fans as the countdown to the big announcement gets closer.