Not sure about cigarette tar but

Paint in France is a ridiculous price.
I needed to paint over a strongly coloured wall in France a couple of
years ago and cheap white emulsion made no impression so we were sold
an oil based white paint which cost a fortune but did the job.
I'm pretty sure it was just white oil based undercoat which you can
get here for £10 for 5 litres in Wickes.
Next time i'm faced with whiting out a pink wall I'll use oil based
undercoat first rather than 3 or 4 coats of emulsion.

Some people think a coat of PVA seals cigarette stains and it has been
discussed here before but I don't think a conclusion was reached.

Brendan.