One official said Mr Johnson had a “penny dropping” moment at a meeting in Luxembourg on Monday.
Mr Watson also said the party must push for a new referendum to take place before a general election.
German newspaper The Handelsblatt reported that a finance ministry document said the German government is expecting Britain to leave the EU without a deal.
In a speech ahead of a secret vote for the next European Commission president, Mr Farage accused German politician Ursula von der Leyen of aiming to make the EU a "centralised, undemocratic, updated form of communism".
Nigel Farage and other Brexit Party MEPs turned their backs at the opening session in Strasbourg while the 'Anthem of Europe' was played at the parliament's first session.
The former leader of the English Defence League blamed a social media ban for his failure to win a seat in the North West.
Brexit: Behind Closed Doors has revealed several moments around the EU negotiations, including the joke about turning Britain into a colony.
The Prime Minister is hoping her much-maligned Withdrawal Agreement will finally be passed.
The Prime Minister wants the possibility of an earlier departure if the UK's withdrawal deal is ratified.
Britain should be as 'difficult as possible' if it stays in the European Union for a long time, Jacob Rees-Mogg has claimed.