French President Emmanuel Macron and German Chancellor Angela Merkel showed their unity on the question of Brexit during a joint press conference here."The withdrawal agreement cannot be renegotiated," declared the French President to members of the press at the Elysee Presidential Palace on Wednesday, a day after British Prime Minister Theresa May's announcement of a possible delay of the UK's departure from the European Union (EU), currently scheduled for March 29, Xinhua news agency reported."If the British need more time, we can consider a request for an extension," he added, saying, "if it is justified."The moment has "come for the British to make choices," insisted Macron, assured to have the support of Merkel.During an address to the House of Commons Tuesday, May admitted for the first time the possibility of a delay of Brexit from March 29 until the end of June.Beyond their displayed unity on Brexit, Macron and Merkel, both under pressure in their respective countries, must deal with numerous subjects which currently divide Paris and Berlin.The German Chancellor also underlined to the gathered journalists the necessary "compromises" to be found.During their working lunch, the two European leaders evoked "the principle subjects on the agenda for the March European Council (European industrial policy, reinforcement of the Euro zone, the fight against disinformation), Brexit, transatlantic relations and the international situation, as well as the defence relationship between France and Germany," said the office of the French Presidency.An update to the Franco-German treaty of friendship and cooperation, known as the Treaty of Aix-la-Chappelle, where it was signed in January, was also on the agenda for the meeting of the two leaders.