Prime Minister Theresa May has said Britain will play a "full and active role in the EU" until it leaves.
Following Brexit, Britain will remain "open" and "outward looking" and is committed to trading freely with other European countries, she said.
The prime minister is attending her first EU summit following the referendum.
Britain will conduct Brexit negotiations in a way that will secure it the best deal, the Prime Minister has said after she was questioned over suggestions that the talks should take place in French rather than English.
The EU's lead Brexit negotiator, Michel Barnier, had previously suggested that divorce talks and documents should all be conducted in French.
However, an EU spokeswoman stressed that it was not an official line and that there is "no language regime for the negotiations".
Theresa May's comments came after her first European Council meeting as Prime Minister.
Asked if she was undermining the UK position, she said: "You can't undermine something that doesn't exist."
The deal would set up a free trade zone between the EU and Canada - and could be an important test for the UK's Brexit negotiations.
European Commission President said an EU-Canada free trade deal would help end Canadian visa restrictions for Romanians and Bulgarians.