MPs have launched two inquiries into the Scottish Government's plans for an independence referendum.
But the move, by the Scottish Affairs Committee at Westminster, was blasted by the SNP, with Nationalist MP Eilidh Whiteford branding it a "partisan inquiry into something which has nothing to do with them".
She hit out after committee members announced their first probe would examine the processes and mechanics by which such a vote would be organised and conducted.
It will focus on issues such as what the process should be for determining the timing of the referendum, how eligibility for voting in it should be determined and what role the UK Government, Scottish Government and Electoral Commission should have in the process.
The second inquiry by the committee will then look at areas which they believe need to be resolved before a referendum takes place in order for voters to make an informed choice.
The SNP won an overall majority in May's Holyrood election, with a promise to hold a vote on independence in the second half of the five-year parliamentary term.
However Dr Whiteford, a member of the committee, claimed the inquiries were "a sideshow from the real issues affecting Scotland".
She added: "This just shows how Labour is obsessing about the SNP when the committee should be investigating the impact of Tory cuts."
Dr Whiteford insisted: "A referendum in Scotland is clearly a matter for the Scottish Parliament and Government, and the referendum that is happening is the one the SNP pledged in the election campaign, which we said will be held in the second half of this parliament.
"That is the platform the SNP stood on in May, and (on) which the people of Scotland gave us a resounding mandate to deliver.
"The days of Westminster committees or Tory and Labour governments telling the people of Scotland what to do are over."
She went on: "Considering the many pressing issues in the areas where the Scottish Affairs Committee could make a useful contribution, it is disappointing they are instead proceeding with a partisan inquiry into something which has nothing to do with them."
However, committee chair Ian Davidson said: "The SNP say they want a referendum on separation to be held but the Committee believes the confusion and uncertainty over Scotland's constitutional future destabilises our economy, deters investment and damages job creation."
The Labour MP added: "Dithering doesn't help Scotland. We believe that no single group or individual has a monopoly of wisdom. Therefore we will conduct an inquiry into how a referendum should be held. We believe a referendum should be fair and open and the rules should not be juggled or rigged to favour either side.
"The committee also believes that Scotland will need a fully informed debate on the merits of separation and will therefore also conduct a second consultation to identify those issues which require resolution or clarification before any such vote is held. Issues already identified include the national currency, the future of pensions and membership of the EU."