While Westminster has been Fox hunting, the dispute over the government's NHS reforms has quietly restarted. The House of Lords began debating the Health and Social Care Bill today and a vote will be held tomorrow. While there is little prospect of the bill being voted down, ministers are concerned that an important amendment tabled by former SDP leader David Owen and the constitutionalist Peter Hennessy could pass.

The amendment is calling for the whole of part three of the bill - the section relating to competition in the NHS - to be referred to a special select committee for further scrutiny. Significantly, as the FT's Kiran Stacey notes, some ministers fear that the amendment could kill off the entire bill. In a letter to peers before today's debate, Richard Howe, a health minister, warned that the "potential for slippage in the timetable carries grave implications for the government's ability to achieve royal assent for the bill by the end of the session. The bill cannot be carried over from this session to the next.

"The House must have proper time to examine the bill but the proposal put forward by Lord Owen could result in delay, which could well prove fatal to it. This is not a risk that I believe this House should take." Under the terms of the amendment, the special committee would report back by 19 December.

Owen has warned that the bill will allow the Health Secretary to "abdicate from all responsibility for the provision as well as the promotion of health-care." In an an article for the NS earlier this year, he previously declared that the Lib Dems would no longer be "the heirs of Beveridge" if they failed to halt or "at the very least, slow down" the reforms.

Labour is likely to vote en masse for the amendment, leaving Owen and Hennessy with around 80 additional votes to win.