Martin Schulz, president of the European Parliament
"We respect the result. We have clarity for the UK to go its own way.
"Now is the time for us to behave seriously and responsibly. David Cameron has his responsibilities for his country, we have our responsibilities for the future of the EU. You can see what is happening to sterling on the markets. I don't want the same thing to happen to the euro.
Geert Wilders, Dutch Freedom Party leader
"Hurrah for the British! Now it is our turn. Time for a Dutch referendum!"
Marine Le Pen, leader of the Front National in France
"Victory for freedom! As I have been asking for years, now we need to have the same referendum in France and in the countries of the EU."
Malcolm Turnbull, Australian prime minister
"The impact on Australia immediately, directly, from a legal point of view, will be very limited because it will take some years for the United Kingdom to leave the European Union, to negotiate an exit. However, we've seen already large falls on stock markets and there will be a degree of uncertainty for some time."
The Irish government
"This result clearly has very significant implications for Ireland, as well as for Britain and for the European Union. The government will meet later this morning to reflect on the result. Following that meeting, the Taoiseach (Irish prime minister) will make a public statement."
Frank-Walter Steinmeier, German foreign minister
"The news from Britain is really sobering. It looks like a sad day for Europe and Britain."
German Vice-Chancellor Sigmar Gabriel
"Damn! A bad day for Europe."
Manfred Weber, leader of the largest group in the European Parliament, the EPP
"Exit negotiations should be concluded within 2 years at max. There cannot be any special treatment. Leave means leave."
Anton Boerner, head of Germany's foreign trade association
"That is a catastrophic result for Britain and also for Europe and Germany, especially the German economy."
Witold Waszczykowski, Poland's foreign minister
"Brexit is bad news for Britian and Europe. It is a sign the EU concept needs to change."
Timo Soini, Minister for Foreign Affairs of Finland
"The nation has had its say."
Speaking of the negotiations that must come between the UK and the EU following this vote, he said: "Any retaliation and whinge is out of the question."
Gerard Araud, French ambassador to Washington
"Reform or die!"