POP / Every night is Saturday night: WPA / The Astoria, London

But every Sat-ur-day . . .' It is indeed the sixth day of the week and the whole club is singing along to 'Father's Day', chanting the irresistible line: 'When he calls me Dad]'

Even those who haven't heard the song before seem to know it instinctively, embedded as it is in a communal memory of classic choruses, the larynx DNA. This is one of the tests of great popular music - you know the song before you've heard it, then are trapped within it, unable to edit the tune from your everyday life, where it circles with phantom tenacity.

'Father's Day' is not just a fine Divorce song, up there in a largely Country pantheon. It's also a great Day of the Week ditty, comparable to 'Monday, Monday' or 'Friday on My Mind'. And of course it has that immortal opening line: 'I haven't always been a lonely man . . .' Songs of this quality usually come in ones, from an artist who can only mint the elixir of pre- cognition once, and is then known forever for a single single. But Weddings Parties Anything (WPA) are exceptional, creating instant classics with facility, then delivering them with brio.

For WPA the sole problem is that 'Father's Day' won an Aria Award as Song of the Year. Aria is an Australian award. In these days of multicultural Globe Beat, it seems a group can still be stigmatised for where they come from - the only apparent explanation for the absence of WPA from eternal No 1 status. Perhaps what we want from Australia is Aboriginal Land Right chants rather than five white boys from Melbourne.

Their new record, Difficult Loves, which they are touring in Europe, is packed with hummability, from 'Step In, Step Out', a song about a shift-working couple, to 'Four Corners of the Earth', which squeezes nostalgia from place names. The ballads are laments filled with that scale, that empty landscape - whether Outback or Midwest - that's essential to the genre.

Michael Thomas is responsible for much of this magic. He founded the group in 1984 and along with Wally, on accordion, is the only original member. A soft-spoken craftsman, he admits to both a love of Martin Amis and a life spent in the pubs of Melbourne's bohemian Brunswick. His songs circle this city's low life; he's the Tom Waits of South Yarra. The numbers, notably Antipodean, prove that drinking all night, watching the rain, losing your girl, are post-hemispherical universals.

In his darkened bedroom he may be a proper songwriter, but in concert Thomas is a proper rock star. With his goatee and faintly puritanical features, he resembles a Frans Hals portrait, albeit one sweating, strumming, cajoling a capacity crowd. WPA reveal an evident relish in their repertoire, a complete belief in the songs that becomes impossible to oppose.

WPA have their fans - including Billy Bragg, The Pogues and Bono, who is quoted as envying Thomas. But, after a few encores, they put one in the embarrassing position of coming on like a Jon Landau left-over. It may not be very post-modern, but is one allowed to have heard the future of rock 'n' roll again, again?

WPA play The Mean Fiddler this Friday and Powerhaus on Saturday