Lords reform: Matthew Oakeshott and Charles Falconer
Lord Oakeshott called Lord Falconer a dinosaur blocking reform as they crossed swords over changes in the Upper House.
The Liberal Democrat claimed the three largest parties had pledged to reform the House of Lords at the 2010 general election.
But the Labour peer said coalition plans must go back to the drawing board as an "inferior second chamber" was a nonsensical idea.
They spoke after reports of Tory MPs said to be against the move.