Shakira has admitted that it is tough being a coach on The Voice.

The sultry singer signed up to appear on the US reality show's fourth series alongside fellow newbie Usher.

Speaking to Access Hollywood, the 'Hips Don't Lie' star revealed that it is hard work being a coach - and being many months into her pregnancy with boyfriend Gerard Piqué doesn't exactly help much.

However, she said that the couple are pleased about participation on the show, adding that she has the resources to see through the stint. Shakira said:

"[It] hasn't been easy, but I have a lot of energy. I can go long hours."

She continued: "I'm thrilled to be here and I'm sure he is too."

As previously reported, Piqué recently claimed on Twitter that Shakira had given birth to their child, which is expected to arrive soon.

However, it turned out to be a trick made on Spain's equivalent of April Fool's Day.