According to The Sunday Times, new British government departments handling Brexit and international trade have not yet been properly setup and staffed.
Britain's exit from the European Union (EU) is likely to face delays and it may be pushed back to the end of 2019, British newspaper, The Sunday Times reported.
Earlier, Brexit (a term commonly used to denote Britain's exit from EU) was expected by politicians early in 2019.
Sources said they had been briefed by ministers that Brexit departments were not ready, hence the exit process will suffer delays.
The UK voted in favour of quitting its membership from the EU on June 23, but Prime Minister Theresa May said she will not invoke "Article 50" this year as the country needs time to prepare for negotiations.
Article 50 of the Lisbon Treaty states that a country exiting the EU will be required to complete the negotiations for new arrangements within two years following the member state's voluntary notification to leave the bloc.
Britain's international trade minister Liam Fox, said in July that early next year could be the best time for Britain to trigger the negotiations to exit.
But Article 50 could be invoked later than that, sources who had been privately warned by ministers told The Sunday Times.
The delays are likely as the new government departments set up to handle Brexit and international trade have not yet been fully staffed.
Elections in France in May and Germany in September, could also push back the timing of Britain triggering Article 50, reported the paper.
Any delay to the Brexit process is likely to draw criticism from the pro-leave side of May's Conservative party, with senior members such as John Redwood calling for a quick departure from the bloc.