It is scandalous that both the UK Parliament and Stormont Assembly are to go on holiday without giving any meaningful detail on Brexit preparations to businesses and the public in Northern Ireland, the SDLP has said.
Last week, Westminster's Northern Ireland Affairs Committee condemned the Government for leaving businesses ill-prepared for the end of the Brexit transition period on December 31.
Under the terms of a protocol in the Withdrawal Agreement designed to avoid border checks on the island of Ireland, Northern Ireland will be a part of the UK's customs territory but will still follow EU customs law and administer the bloc's customs rules at its ports.
The region will also follow EU single market regulations on goods.
The Government has acknowledged this will mean more regulatory checks on some goods entering Northern Ireland from the rest of the UK.
MPs on the NI Affairs Committee called on ministers to provide more detail and clarity to businesses on trading arrangements by October 1 to ensure the "unfettered" transport of goods between Northern Ireland and Great Britain.
Party Brexit spokesman Matthew O'Toole has written to Arlene Foster and Michelle O'Neill, as well as UK minister Michael Gove to complain about the "abysmal lack of information provided to the public and business - as well as the complete failure to update the Northern Ireland Assembly - with less than six months until the planned end of the transition period".
In a letter to Mr Gove, Mr O'Toole criticised "the shameful failure of the UK Government to provide any clarity on the operation of the Ireland protocol to local business, while also stridently refusing to countenance any extension of the Brexit transition period".
Mr O'Toole said that despite the UK Government's claims to have prioritised Stormont consent, "Mr Gove and his fellow Tories have not even acknowledged the Assembly's motion calling for a Brexit transition extension".
A simultaneous letter sent to the local First Ministers "laments the lack of any public advocacy from the leaders of devolved Government on behalf of Northern Ireland's interests in relation to Brexit".
The MLA said there had not been a single update to the Assembly on Brexit preparations "despite the huge risk presented to Northern Ireland and the rapidly shortening closing timeframe".
The Assembly is due to go into recess later this week. Mr O'Toole said: "I have written to both Michael Gove and the First Ministers in growing despair at the total absence of either information or transparency on what is happening in relation to Brexit and the implementation of the Protocol.
"Gove has waxed on about his desire to serve Northern Ireland's interests, but has treated our people and our industry with little more than contempt. I have set out a series of basic questions to answer.
"In truth we have come to expect little more from ideological Brexiters in Government. But people here were entitled to think that the return of an Executive and Assembly would at least mean more of an opportunity for real local accountability and action to protect our interests."
Separately, Ireland's Justice minister Helen McEntee has said paramilitary violence could reignite in Northern Ireland if the UK and EU fail to agree a new "toolbox" for cross-border police co-operation before the Brexit transition period ends.
"The threat of a resurgence in paramilitary activity in Northern Ireland is very real and the ability to counter that threat could be seriously undermined with the loss of the toolbox provided for by EU instruments," she told the Sunday Times.