DMK President M Karunanidhi today described BJP's Prime Ministerial candidate Narendra Modi as a 'hardworker' and a 'good friend.'br br Karunanidhi's response came in an interview to one of the leading Tamil dailies 'Dinamalar,' in which the 90 year-old DMK patriarch also refrained from commenting on a possible tie-up with the saffron party post-elections.br br "The hectic election campaign by Modi shows he is a hardworker.