1994 Other Nissan Models nissan micra starter motor

Engine Mechanical problem
1994 Other Nissan Models Front Wheel Drive Manual 16234 miles

i have a 1994 1.0l nissan micra it has low milage but over the last few weeks it wont start all i get is a whirring noise from the engine presumably the starter motor. after some time it will start sometimes straight away or i have to fight with it. once its started it tends to be fine for the rest of the day and will start again first time. the problem is becoming more frequent now. thanks