European Union leaders have given the go-ahead for Brexit talks to move onto the second phase, paving the way for crucial discussions on trade.

Donald Tusk, European Council president, tweeted the news after a meeting of the other 27 EU leaders in Brussels.

Tusk also congratulated British Prime Minister Theresa May on the progress in his Tweet.

EU leaders have confirmed that "sufficient progress" has been made in the first phase of Brexit talks.

The discussions about Britain's future outside the bloc will now include trade and security.

It's thought the next round of talks on a transition period after the UK leaves in March 2019 could begin as early as next week.

According to the BBC, European Commission President Jean-Claude Juncker said this process would be "significantly harder".

Junker added that the EU's initial priority was to "formalise the agreement we have now" on issues such as citizens' rights before starting negotiations on a future relationship after the UK leaves in March 2019.

To get to the second phase, Britain had to satisfy the EU on three issues - the UK's Brexit bill, the rights of EU citizens and the Northern Irish border.