A "deeply off the record" tweet from NSW Opposition Leader Barry O'Farrell was posted on Twitter today in an embarrassing gaffe in which he appeared to call redheaded Prime Minister Julia Gillard a "ranga".

The Liberal Party has yet to select its candidates for the federal seats of Greenway and Parramatta despite the imminent announcement of an election.

Barry O'Farrell ... a bit of a tweet Credit:Peter Rae

The mistake came after Mr O'Farrell appeared to publicly answer a private question on the delays from Fairfax radio reporter and keen tweeter Latika Bourke.

Mr O'Farrell wrote: "deeply off the record - I think the timetable & struggle to get candidates reflects internal poll - pre & post the ranga".