Demi Lovato and Selena Gomez
Demi Lovato and Selena Gomez

American pop star Demi Lovato has come forward to support best friend Selena Gomez after it was revealed that the singer went to rehab last month.

The 21-year-old Come and Get It singer was admitted at The Meadows treatment center in Wickenburg, Arizona on 5 January.

"Selena voluntarily spent time at Meadows but not for substance abuse," a spokesperson for the singer told People.

During an interview with Mario Lopez from Extra, Lovato said, "Selena and I have such an amazing friendship and have known each other for 14 years and I love her to death."

She also took to Twitter to offer some encouraging words.

"Weakness is living in denial. Only the strongest people ask for help," she tweeted.

In December, Gomez had cancelled her tour of Asia and Australia stating personal reasons. She was scheduled to travel across the continents to promote her recent album Stars Dance.

"My fans are so important to me and I would never want to disappoint them," Gomez said in a statement then. "But it has become clear to me and those close to me that after many years of putting my work first, I need to spend some time on myself in order to be the best person I can be. To my fans, I sincerely apologise and I hope you guys know how much each and every one of you mean to me."