2006 Peugeot 307 loss of power

my Peugeot 307 HDI starts up on first turn of the key after been stood over night on my drive it runs perfectly for about a mile / mile and a half then it suddenly looses power if I am doing less then 25 mile an hour it will cut out if I am doing 30 mile an hour or there about the car starts shunting with very little power but I can normally keep it going for about 150 yards then it clears it's self and runs perfect for the rest of the day if it cuts out I have to stop the car at the side of the road it will then start on the first turn of the key and run perfect for the rest of the day. can anyone help me with the problem I have please. I am driving a Peugeot 307 HDI diesel 2006 plate. any help will be appreciated Thank you.