A dramatic video has emerged of a motorcyclist slipping on a country road and crashing her bike near Carmarthen, Wales, UK.

The footage, shot with a helmet-mounted camera late last month, captures the moment the biker loses control of her bike and slides on the road over several metres.

"Tyres were cold could possibly have slipped on oil, water or even a tiny amount of farm waste like manure," she wrote online.

"Felt my wheels slide panicked and headed straight into the ditch once it was too late to recover."