Rival camps in Greece are set to hold major rallies in Athens ahead of Sunday’s crucial referendum on an international bailout deal.
PM Alexis Tsipras is expected to be at one rally to support the “No” vote, opposing the terms.
EU leaders have warned that a “No” vote could see Greece leave the eurozone.
This has been a lightning campaign. Greece has been in deadlock with its creditors for months but only called the referendum last week.
The BBC’s Chris Morris in Athens says there has been no referendum campaigning as such – just a few chaotic days as supporters and opponents of the governing Syriza party have jostled for position.
Campaigners are now racing to reach voters before time runs out, with “Yes” and “No” posters vying for space in Athens.
On Friday, competing rallies are expected to be held in Athens city centre. Our correspondent says they will try to define what the referendum is really about.
One undecided voter, Costas Christoforidis, told AP: “If it’s saying ‘No’ to austerity, then it’s a ‘No’ from me too. But if we are rejecting Europe, I disagree with that.”
Many protesters have already taken to the streets in the past days. Some 6,000 Greek Communist Party supporters held a demonstration on Thursday, calling on referendum voters to cast invalid ballots.
Brief scuffles broke out between riot police and a small group of demonstrators.
A “No” rally took place at the city’s university, attracting more than 1,000 people.
However, despite the campaigning, there is still a chance the referendum may yet be suspended.
Greece’s top administrative court, the Council of State, is due to decide on the legality of Sunday’s vote – whether it breaches the constitution.
Human rights body the Council of Europe has already said the referendum would “fall short of international standards” if held as planned, citing the short notice given to voters and the lack of clarity in the question to be put to voters.
Divisions in Greece have sharpened ahead of the vote. One poll cited by euro2day.gr said 47% of people were leaning toward a “Yes” vote, with the “No” camp at 43%. A previous poll suggested the “No” camp had a shrinking lead.
Mr Tsipras has said that a strong “No” vote will help lead to a “better agreement” with creditors.
“Our efforts are focused on overcoming the crisis as fast as possible, with a solution that preserves the dignity and sovereignty of our people,” he said.
But EU leaders have warned that a “No” vote on Sunday may see Greece leave the eurozone, something Mr Tsipras says he does not want to happen.
His opponents in Greece have said they believe he is making a mistake.
In a speech endorsing the “Yes” campaign on Thursday, former Greek PM Costas Karamanlis said the world would “consider a ‘No’ vote to be a withdrawal from the heart of Europe, the first step toward euro exit”.