It is doubtful that Brexit will be completed in two years' time, says Caroline Flint.
Speaking on The Daily Politics today, the former Labour Europe minister said it is unlikely that the Government will organise a free trade deal with the European Union by April 2019.
The Brexit process
Her comments come in response to today's announcement that Prime Minister Theresa May will trigger Article 50 on Wednesday March 29th.
She will make a statement to the House of Commons on Wednesday afternoon following Prime Minister's Questions to inform the House of her plans.
After that, the Prime Minister will then write a letter to the President of the European Commission Donald Tusk to tell him the Government wishes to begin negotiations.
The European Commission may be delegated with the task of managing Britain's EU exit.
Brexit Secretary David Davis will lead the negotiations with the EU on behalf of the Government.
But Jill Rutter from the Institute for Government Reform warned on The Daily Politics Parliament may not have time to legislate non-Brexit related legislation.
This is due to the complexities of transferring EU law into British law.
No Brexit in two years
Former communities secretary Eric Pickles said he is pleased the Prime Minister is getting on with leaving the EU.
But he added: 'Negotiating with the EU will be very complex. Not everything will be sorted out quickly.'
Flint said a lot of work will be completed over the next two years.
But she said we will 'only have headlines by two years.'
The Labour MP said there will be six years of transitioning from the EU before Britain finally quits the bloc altogether.
This may mean the UK will have to resort to temporary EEA membership, meaning we remain a member of the Single Market whilst being able to repeal the Common Agricultural Policy and Common Fisheries Policy.
She added: 'It will not be over in two years' time.
'The Labour Party's position was absolutely the right one as we were concerned about the rights of EU nationals to reside in this country.'
However, UKIP MP Douglas Carswell said he is optimistic Brexit will be completed in two years.
He said the Government will be able to legislate the Great Repeal Bill and exit the EU at the same time.
But Pickles said any meaningful negotiations may not commence until autumn this year.
Delays to leaving
Article 50 is the mechanism which allows a country that has decided to leave the EU to begin the process of exiting the superbloc under the 2007 Lisbon Treaty.
This treaty was signed by former Labour prime minister Gordon Brown.
Britain voted to leave the EU on June 23rd 2016.
May has made Brexit her top priority since taking over from her predecessor, David Cameron, in July last year.
But it has taken the Government nine months to prepare to leave the EU.
This was due to no contingency plans being formed when Cameron was prime minister in the possible event of a Leave vote.
Leaving the EU has also been delayed by challenges from businesswoman Gina Miller, who challenged the Government in the High Court and the Supreme Court.
She wanted clarification over whether or not the Prime Minister can trigger Article 50 without parliamentary consent.
The Brexit Bill was passed into after receiving Royal Assent last Thursday.
