Britain is due to leave the EU on March 29 and no divorce agreement is yet in place.
British Prime Minister Theresa May is heading to a summit of EU and Arab League leaders in Egypt this weekend, but will not try to hijack the gathering with Brexit talks, officials insisted on February 20.
The two-day first-ever summit between the European Union and the League of Arab States, in the Red Sea resort of Sharm el-Sheikh, starts on February 24.
A senior British government official insisted May would not attempt to talk Brexit with fellow European leaders, more than 20 of whom are expected to attend.
Britain is due to leave the EU on March 29 and no divorce agreement is yet in place. May was in Brussels on Wednesday for talks.
"There are important shared challenges to discuss with the League of Arab States like security cooperation," the official told reporters.
"This is not a meeting about Brexit and the prime minister is not going to seek to turn it into one.
"At summits, the PM always holds a series of bilateral meetings and conversations and she will, of course, continue to engage her fellow leaders in relation to Brexit.
"But this isn't a European Council meeting and it isn't somewhere that European Council decisions are going to be made."
Irish Prime Minister Leo Varadkar, whose country is at the heart of the current dispute between London and Brussels, is expected to take part in the summit.EU President Donald Tusk and European Commission president Jean-Claude Juncker will also attend.