3 July 2015From the sectionEurope Rival camps in Greece are set to hold major rallies in Athens ahead of Sunday's crucial referendum on international bailout terms. Prime Minister 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. Greece's economy is already being squeezed after the country lost access to fresh funds. Banks have been shut and limits imposed on cash withdrawals. Greece has been in deadlock with its creditors for months but only called the referendum last week. There has been no campaigning as such, the BBC's Chris Morris reports from Athens - just a few chaotic days as supporters and opponents of the governing Syriza party have jostled for position. Both sides are now racing to reach voters before time runs out, with"Yes" and"No" posters vying for space. A poll published in Ethnos newspaper on Friday showed the two sides evenly split, with the"Yes" vote at 44.8% and the"No" vote at 43.4%. But the same poll showed 74% in favour of staying in the euro, with just 15% choosing a return to a national currency. Despite the campaigning, however, there is still a chance the referendum may be suspended. Greece's top court, the Council of State, is due to rule on the legality of Sunday's vote and 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. There have already been rival protests in recent days. Mr Tsipras has said that a strong"No" vote will help lead to a"better agreement" with creditors. "If the'Yes' vote wins the banks will open with a deal, which will not be viable, but if that is the decision of the Greek people, either from fear or from pressure, or choice, we will respect it," he said.