Labour and the government are still at loggerheads over the need for a judge-led inquiry into the Libor interest rate row, after both sides refused to budge on the issue.
Ed Miliband used PMQs to present an alternative twin-track plan for the inquiry while David Cameron encouraged him to accept the result of an upcoming Commons vote he is sure to lose.
"Whenever these scandals happen, he is too slow to act and it's in the interests of the wrong people," the Labour leader said.
"If he fails to order a judge-led inquiry, people will come to one conclusion - he simply can't act in the national interest."
Cameron replied: "Everyone can see what is happening here. The party opposite wants to talk about absolutely everything but their record. We may have found the Higgs Boson particle but Labour hasn't found its sense of shame.
"People will take a very dim view of an opposition party which stands in the way of an inquiry because they don't want their dirty washing done in public."
During the session, Miliband tried to satisfy Cameron's argument that the public needed a "swift" inquiry into the Libor scandal by suggesting a twin approach.
One part of the judge-led inquiry would look into the interest rate scandal specifically and report by Christmas, while a second party would look at the broader cultural issues in the banking sector and report later.
Cameron said he would consider the proposal but went on to attack the Labour leader in fairly strong terms, suggesting he is not prepared to accept the plan.
Instead, he encouraged Miliband to pledge to accept the result of a Commons vote on the inquiry which will be taking place later.