MPs are to vote on the type of inquiry to be held into the Barclays Bank rate-rigging scandal.
After a row between the government and Labour, MPs will choose whether to hold a judge-led inquiry, favoured by the opposition, or a parliamentary one, favoured by ministers.
It follows the appearance of former Barclays chief executive Bob Diamond before a committee of MPs.
Voting is expected to take place on Thursday afternoon.
Last week, regulators in the US and UK fined Barclays £290m for attempting to rig Libor and Euribor, the interest rates at which banks lend to each other and which underpin trillions of pounds worth of financial transactions, during the middle and end of the last decade.
Bob Diamond, who quit Barclays on Tuesday, told the treasury select committee the behaviour of those responsible for rate-rigging at the bank was "reprehensible" and he felt "physically ill" when reading incriminating emails from traders.
'Too narrow'Labour and the Conservatives have clashed over the terms and nature of an inquiry into the scandal surrounding Barclays.
During Prime Minister's Questions, David Cameron said a single parliamentary inquiry into the "appalling" events would be the most "swift and decisive" course of action.
Analysis
You know what it's like, you wait for an inquiry to examine the events leading up to an international financial scandal, then two come along at once.
The government announced it wanted a parliamentary inquiry - led by the Tory MP Andrew Tyrie - which would include peers and other MPs.
Its job (probably) to investigate the circumstances surrounding the rate-fixing at Barclays.
It would have the power to call witnesses under oath and it would get to work quick. The aim being to wrap up by Christmas.
Labour wanted more, a full independent public inquiry, Leveson-like.
In a sign of the importance he attached to his work Mr Tyrie said he would only do it if he got cross-party support. He wanted to avoid any hint of a Tory whitewash.
But that support hasn't happened. Not yet anyway. Now the treasury select committee is considering an inquiry, led by its chairman... Andrew Tyrie.
Underlying it all is briefing and counter-briefing, from Labour and Tory sides, on who is to blame for what went wrong.
But Ed Miliband said this was "too narrow" and a much wider judicial probe into the culture of banking was needed.
Mr Miliband has proposed a two-stage public inquiry. This, he said, would focus on the specific allegations facing Barclays to report by the end of 2012 followed by a broader year-long probe into banking standards and practices.
The House of Lords has already rejected a Labour attempt to amend the Financial Services Bill which would have led to a judicial inquiry.
The government motion to be debated on Thursday, if passed, would set up "a joint committee of the two Houses" which would look "into professional standards in the banking industry".
Leader of the House of Commons Sir George Young said it would produce findings "over the next few months, instead of waiting for a decade after the scandal itself to get some answers".
Labour wants "an independent, forensic, judge-led public inquiry... into the culture and professional standards of the banking industry" to be completed within 12 months and paid for by banks.
'Simple choice'In addition to Ed Miliband, it has been signed by independent MP, Sylvia Hermon, the nationalist parties and Caroline Lucas from the Green Party.
BBC political editor Nick Robinson said Labour was likely to lose the vote on the judicial inquiry if the Lib Dems, as expected, backed their coalition partners.
If this happened, he added, Mr Miliband would face a "simple choice" on whether to accept the parliamentary probe or risk being blamed for voting down an inquiry.
The senior Tory MP chosen to lead the parliamentary inquiry, treasury committee chairman Andrew Tyrie, has indicated that he might rule himself out of the job if it does not have Labour's backing.
The Serious Fraud Office is also considering whether to bring criminal charges, while Barclays has said it will conduct its own "root and branch review".
