Pop singer Justin Bieber lashed out at H&M over clothes featuring the Canadian artist's image and lyrics, saying the Swedish fashion giant had not obtained his approval.

"The H&M merch they made of me is trash and I didn't approve it," Bieber wrote in an Instagram story on Monday, encouraging his 270 million followers not to buy it.

"As with all other licensed products and partnerships, H&M followed proper approval procedures," an H&M spokesperson said in a written comment to Reuters.

The online store of the world's second biggest fashion retailer is offering hoodies, t-shirts and sweatshirts with pictures of Bieber or quotes from his lyrics like "I miss you more than life" from the song "Ghost" for prices between 79.99 and 349 Danish crowns ($49.8-$114).