Nicole Scherzinger - Nicole Scherzinger Splits From Lewis.

Nicole Scherzinger and Lewis Hamilton have split up.

The Pussycat Dolls star and her 25-year-old British racing driver lover have ended their 20-month romance because they want to "focus fully" on their own careers.

A statement from their spokesperson said: "They have decided to go their separate ways. They want to focus fully on their careers and will remain close friends."

Friends of the famous couple are shocked because Nicole and Lewis loved each other implicitly and were very happy.

One told the Daily Mirror newspaper: "It's sad because they did love each other. When you saw them trackside together they were always laughing and Nicole would give him a little peck on the cheek before the race. But they had to be realistic. There was no way they would continue their careers and stay together - it was too stressful. No one else is involved - their careers just got in the way."

In December, it was reported the couple hadn't seen each other in almost a month and even scrapped plans to spend Christmas Day (25.12.09) together.

At the time, a source said: "Lewis and Nicole have had a few problems for a while now. They love each other dearly but have incredibly busy schedules.

"Hopefully after a month apart, they will come to their senses and give things another go."

Lewis - who lives in Switzerland, while Nicole is based in Los Angeles - has previously blasted speculation their relationship was in trouble.

The Formula One ace said: "This is bulls**t. We are still together."

The couple first met at the MTV Europe Music Awards in November 2007 and started dating in May 2008.