(CNN) German Chancellor Angela Merkel has warned Britain not to hold any "illusions" about what Brexit means for its future, adding that it "cannot and will not have the same rights as a member of the EU."
Addressing the German Parliament Thursday, Merkel said negotiations between the UK and the EU would "demand a great deal" of effort from both sides over the next two years, but that she wanted them to be "fair and constructive."
Merkel's comments come as EU leaders prepare to meet Saturday in Brussels, Belgium -- without UK Prime Minister Theresa May -- to finalize their negotiating position, before formal talks to end Britain's 44-year membership of the bloc begin.
Merkel said those negotiations were expected to commence after the UK snap general election on June 8.
"We have an interest in a prosperous and successful United Kingdom. In one word, we will conduct fair and constructive negotiations and that's precisely what we also expect from the British side," she said.
The size of the so-called Brexit bill is expected to be a key sticking point in negotiations.
But Merkel insisted that talks must, from the outset, include Britain's financial obligations to the bloc, the AFP news agency reported.
She also stressed the need to safeguard the interests of German citizens living in Britain (there are an estimated 100,000 in the country) and to give them clarity about their future status as soon as possible.
"In return, we will of course be ready to give a fair offer to Britons living in Germany and other European member countries," she said.
Merkel said she expected "a strong signal of unity" after the European Council meeting Saturday, at which the remaining 27 EU members will adopt the bloc's draft negotiating guidelines.
As election campaigning heats up, May and her governing Conservative Party are seeking to position themselves as offering the "strong and stable leadership" needed as Britain enters thorny Brexit negotiations.
Speaking in the House of Commons Wednesday, May warned that the opposition Labour Party would condemn Britain to a "chaotic Brexit" if it won the election, saying: "Every vote for me is a vote to strengthen our hand in negotiating the best deal for Britain."
Labour meanwhile has promised to ditch May's plan if it wins the election, saying it will seek a softer departure from the European Union.
Labour's Brexit spokesman Keir Starmer said this week that, if elected, his party would guarantee EU nationals living Britain the right to remain in the UK after the split, and would be open to retaining the benefits of the EU's single market and customs union.
Last month, EU Commission President Jean-Claude Juncker told the BBC that Britain would need to stump up roughly £50 billion ($62.4 billion) as it leaves the European Union in order to honor its budgetary commitments.
EU member states pay into a communal budget, which finances infrastructure projects, social programs, scientific research and pensions for EU bureaucrats. The bloc's budget is negotiated to cover a period of years, with the current agreement extending to 2020.
Britain pays roughly £10 billion a year ($12.5 billion) a year more into the budget than it receives in benefits -- a fact often cited by supporters of Brexit.
The UK government formally served divorce papers on the European Union on March 29, signaling the beginning of the end of the decades-long relationship.