The timetable for MSPs to scrutinise Scottish Government spending plans has become "almost dysfunctional" as a result of delays in the publication of the draft Budget, the Finance Secretary has been told.

Derek Mackay came under fire from members of Holyrood's Finance Committee after he told them the proposals for 2017-18 - the year Scotland gets new powers over income tax - would not be published until shortly before Christmas.

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The Government will have to work "incredibly hard" to produce draft plans within Mr Mackay's timetable of three weeks after UK Chancellor Philip Hammond makes his Autumn Statement, which is not expected to take place until late November or early December.

The Finance Secretary committed to do that but said: "I will not have a draft budget to scrutinise until I have the data that is required from the Chancellor's Autumn Statement."

In previous years, the Scottish Government has published its draft Budget earlier in the Holyrood calendar, with proposals for the 2014-15 budget unveiled in September 2013.

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Previous finance secretary John Swinney did not announce his spending plans for 2016-17 until December 2015, and with the 2017-18 Budget not being published till December, opposition MSPs complained about having less time to examine the detail of the proposals.

Conservative MSP Alex Johnstone told the committee: "The timescale that he is adopting and the timescale for the committee's scrutiny is now at a point where the system is almost dysfunctional."

Fellow Tory MSP Adam Tomkins said the Government is "asking for a massive curtailment of parliamentary time in terms of the extent of the period available for this parliament to scrutinise your draft Budget".

He told the Finance Secretary: "Thinking about the magnitude of the harm that will be done to Scottish democracy by this Parliament not being able to scrutinise your budget proposals effectively, you are asking for something that is going a little further than is necessary."

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The Organisation for Economic Co-operation and Development's (OECD) "ideal" length of time for parliaments to scrutinise budgets is "between three and four months", Mr Tomkins said.

Green MSP Patrick Harvie said the timetable being proposed meant committees would "effectively have the last week of term before Christmas and the first week of term after Christmas as the only opportunities to take evidence on the Budget".

Mr Mackay said he had not been able to obtain "further clarity on timescales" for the Autumn Statement from the Chancellor and knew "nothing of substance as to what might be in the Chancellor's statement".

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He told the committee: "Of course, I have expressed the difficulties that causes this parliament and the government to take forward our budget."

He insisted he could not produce an "accurate" draft Budget until after the statement, warning the economic uncertainty caused by the Brexit vote could see cuts made to Scottish spending.

In previous years the UK Government's Autumn Statement has resulted in extra money coming to Scotland but the Finance Secretary said: "I don't get a sense that is what is about to happen in this Chancellor's Autumn Statement."

He added: "For this year we are facing an unprecedented economic challenge because of the Brexit vote.

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"I am convinced, from all the statements, that there will be a major financial adjustment and there will be inevitable knock-on consequences to the government's budget."

Mr Mackay suggested some information could be given to the Finance Committee before the publication of the draft Budget.