Theresa May has insisted she will be "robust" in Brexit talks as she dismissed "noises off" after Brussels set out plans that would allow it to sanction the UK during transition.
The Prime Minister's inner "war cabinet" of senior ministers is meeting on Wednesday to chart a course through some of the most difficult issues in the Brexit process.
Brussels released papers showing it wants to put in place a method to rapidly curtail the UK's single market benefits if it breaches agreements on a transition deal.
Asked during Prime Minister's Questions if she would see off any "threats" from the European Union, Mrs May said: "We will be robust in our arguments.
"As I have said right from the very beginning we will here noises off, we will hear all sorts of things being said about positions that are being taken.
"What matters is the positions we take in the negotiations as we sit down and negotiate the best deal. We've shown we can do that. We did it in December and we are going to do it again."
Under plans released by the European Commission, Brussels would be able to restrict the UK's access to the single market without going through the lengthy European Court of Justice (ECJ) legal process.
The position paper on transitional arrangements in the withdrawal agreement said there should be a "mechanism" allowing the EU to "suspend certain benefits" of single market membership during the transition period.
Such a move would be considered if referring the matter to the ECJ "would not bring in time the necessary remedies", according to the document, which sets out the EU's position on a transition deal in legal language.
The document also said the UK would only be "consulted" when decisions are made on fishing quotas during the period.
Mrs May is chairing the European Union exit and trade (strategy and negotiations) sub-committee in sessions on Wednesday and Thursday to thrash out the UK's position on crunch issues regarding the future relationship with Brussels.
Wednesday's talks are expected to focus on immigration and Northern Ireland, with the future partnership being considered on Thursday.