Britain's exit from the EU will begin "when we're ready", the Government's main legal adviser has said as he denied confusion over the timing.
Attorney General Jeremy Wright also explicitly ruled out a veto for Scotland over when the Brexit process is started - via Article 50 of the Lisbon Treaty - amid Tory fears that the UK will be "held to ransom" by the SNP.
Mr Wright faced a series of questions about the process after Brexit Secretary David Davis suggested Article 50 could be invoked before or by the beginning of next year, although Prime Minister Theresa May has insisted it will not happen before the end of this year.
Speaking in the Commons, the SNP's Peter Grant (Glenrothes) asked Mr Wright to clarify whether Mrs May or Mr Davis is right over the Government's position on Article 50.
Mr Wright replied: "I don't think there is any confusion.
"What we must do is make sure there is clarity about the United Kingdom's position going into these negotiations, that we've done that work before we begin them."
He added: "It is for the United Kingdom to determine at which point Article 50 is triggered. We should do so when we're ready."
Alison Thewliss, SNP MP for Glasgow Central, pushed for answers on Scotland's role given the country's support for Remain.
She asked: "The Prime Minister has indicated that she'll not trigger Article 50 in the UK until there is a UK approach to Brexit.
"Do you agree that a legislative consent motion is required before the Government has legal authority to trigger Article 50?"
Mr Wright said all of the UK's devolved administrations should take part in the process of developing the UK's approach to the Brexit negotiations.
He added: "But that does not mean that any of the parts of the United Kingdom have a veto over this process and so consultation most certainly, but veto I'm afraid not."
Tory MP David Nuttall (Bury North) voiced concerns over the approach of the SNP, telling Mr Wright: "I'm quite happy with the Government consulting with the devolved administrations.
"But what concerns me is that we don't finish up being held to ransom by the Scottish nationalists.
"The point is that whatever the Government try and do they will never be able to satisfy the Scottish nationalists.
"Can you please reassure me and my constituents who voted overwhelmingly to leave the European Union that their wishes will not be frustrated by the Scottish National Party."
Mr Wright said the Prime Minister has been clear the UK will leave the EU, adding: "That means all of the United Kingdom."
He reiterated all parts of the UK should be allowed contribute to the negotiations.