The Taoiseach Enda Kenny has been accused of "clowning around Europe" and "urinating on the Seanad".
The outburst by Fianna Fáil Senator Mark McSharry led to rowdy scenes in the upper house this afternoon.
Mark McSharry called on the order of business for a debate on the behaviour of the Taoiseach in recent weeks.
He said: "We see him clowning around Europe, as it has to be said, acting like a clown, turning a circus ring of a government."
It was then that chaos descended with three or four minutes of shouting and roaring from across the house.
The Sligo-based Senator accused Mr Kenny of accepting Brian Lenihan's accolade for putting the country back on the path to recovery.
Senator McSharry's microphone was turned off, but he could still be heard accusing Mr Kenny of "urinating" on the Seanad and he said Cathaoirleach Paddy Burke was facilitating it.