Llanelli Rugby Club have issued legal proceedings against the Welsh Rugby Union to prevent the governing body from imposing their proposed four-province structure for next season and beyond.

The club took their case to the British High Court yesterday and a writ was due to be delivered to the WRU later today stating the union were acting unlawfully in pursuing a four-team structure.

Llanelli chief executive Stuart Gallacher said: "The WRU knows this proposal is not viable. It admits to blockages with the European Rugby Cup and broadcasters and we, along with other clubs, have made clear our intention to take legal action if they persisted.

A spokesman for the WRU last night confirmed the union had referred the matter to its lawyers and declined to comment further.