The 48-year-old singer has enjoyed huge hits in the U.K. and Europe, but has failed to replicate that sucess in her native country. And in a new interview, Anastacia speculated about the reason for her decreased popularity in America.

"I don't know the exact reason but I can give you an idea of what may have happened," she told the Official Charts Company. "My first record was scheduled to be delivered in America, radio and everything. I was with Sony Worldwide but as I was an American signed artist, so they were starting with America.

"Either something happened with radio promotions, somebody made somebody mad; something happened with my release. I don't know anything about it and I can't understand it. Simultaneously my name was a part of it so I think I was blacklisted from radio."

The I'm Outta Love star has enjoyed 14 hits in the Top 40 of the U.K. charts over the years. However, she has yet to top the charts, although she insists she isn't too worried about the chart performance of her tracks.

"I don't look at the 1s, 2s and 3s... I look at paying my rent! Being able to still have a career after 20 years; those are the things I focus on," she added. "If a Number 1 can happen in life somewhere down the line, that's cool, but that's never been my goal. It doesn't spur me on. I was very lucky to have the 'out of the box' success that only happens to a few people in their lives and I cherish that."

Anastacia is now gearing up for a second leg of her Ultimate Collection tour next year (17). She will delight fans with renditions of her biggest hits, and insists she is looking forward to getting another tour of the U.K. on the road.

"Being an American and being that my career has been very successful in the EU, being here (London), I felt so comfortable in a country where language wasn't a barrier," she said. "It reminded me of New York, Chicago - very metropolitan. Then the humour of the UK is something I love and adore. I wanted to gain the diplomacy and demureness of your culture, I don't know if... it has definitely not worked! But I'm hoping 10 years down the line, I know what forks to use!"