President of the European Commission Jean-Claude Juncker, left, chats with President of the European Parliament Martin Schulz | Sean Gallup/Getty Images EU leaders to UK staff: We’ll try to protect you after Brexit Heads of the main institutions wrote all officials promising to fight for their jobs.

Top EU officials acted quickly Friday to reassure British staffers working in the main European institutions about how the Brexit vote would affect their job.

"I know that many of you are concerned about your future after this vote," wrote European Commission President Jean-Claude Juncker in an email to staff, obtained by POLITICO. "I fully understand that. So I want to send a clear message to you, colleagues, and especially to colleagues of British nationality."

Juncker told staffers that according to EU rules "you are 'Union officials.' You work for Europe. You left your national 'hats' at the door when you joined this institution and that door is not closing on you now." He promised to "support and help you in this difficult process. Our staff regulations will be read and applied in a European spirit."

Job security is less certain for British staffers in the European Parliament, where the 73 U.K. MEPs will lose their seats when the Brexit process is complete. European Parliament President Martin Schulz assured British staffers that he will defend their interests during the negotiations for the U.K. to exit the EU.

In an memo obtained by POLITICO, Schulz thanked British staffers for their "loyalty."

"You have shown your loyalty to the European idea in your hard work for the success of the European Parliament," Schulz wrote. "In this spirit of reciprocal loyalty, I will work together with the Presidents of the European institutions to ensure that we can all continue to count on your outstanding talent, experience and commitment."

Schulz promised to defend their "interests" during the exit procedure, which is slated to last about two years, once it is activated. Britons voted to leave the EU in a referendum on Friday and leaders from the EU institutions have urged them to submit their request for withdrawal immediately. The fate of the thousands of U.K. staffers working in the Council, Parliament and Commission hangs in a balance until the deal is settled.

"I can assure you that in those negotiations, I will do my utmost to defend your interests," he wrote.

Jeppe Tranholm-Mikkelsen, the secretary general of the EU Council of Ministers, wrote staff telling them he would appoint a special task force to manage the negotiations for the U.K. exit.

"I know that many colleagues, in particular those who are British nationals, are very concerned today," Tranholm-Mikkelsen wrote. "I cannot prejudge of [sic] the position of the Council, but I would like you to know that, for me, all [general secretariat] colleagues are European Union officials, independently of the nationality on the basis of which they were recruited."