PARIS // Most delegates will follow instructions from their government when deciding which city should host World Expo 2020 – but final presentations may sway some of them in Paris on Wednesday.

The 20-minute presentations by the four competing cities – Dubai, Sao Paulo in Brazil, Izmir in Turkey, and Yekaterinburg in Russia – will start off the crucial day.

They will be the focus of the second day of the general assembly proceedings of the Bureau International des Expositions (BIE), the international organisation responsible for overseeing, regulating and selecting the winning city.

“The content, the quality and the emotional impact of final presentations can influence the vote during the second and the third rounds in the case of delegates who after having followed official instructions will make the choice in an autonomous way,” said BIE spokesman Ivan Prostakov.

The host city will be announced after voting by delegates of 168 member nations of the BIE.

“Final presentations will remind BIE delegates the main points of candidates’ projects. There are no specific rules on the presentations scenarios considering that at the time of the vote delegates have already had precise instructions from their capitals. It does not mean that the presentations are purely symbolic and simply mark the end of the bidding campaign,” Mr Prostakov said.

He explained that a few countries could decide just before the voting.

“Usually BIE delegates come to the vote with precise instructions from their capitals,” Mr Prostakov said.

“Maybe only a few countries take the final decision just before the voting procedure. In any case, when a run-off election is possible, some countries can have instructions not for all rounds and the decision could be taken during the voting procedure.”

This scenario could arise if the candidate its government has selected is voted out in the initial rounds.

Abiding by their country’s decision also ensures a lack of bias and a fair ballot in the tightly contested proceedings.

“The official instructions from capitals on the vote ensures the objectivity of BIE delegates member countries,” Mr Prostakov said.

After the four cities complete their presentations, the proceedings will break for lunch which will be followed by the vote conducted by electronic ballot.

The voting is organised in the BIE’s general assembly conference room where delegates make their decision in special cubicles. While the voting room is not locked, only BIE delegates and secretarial staff can access the area.

The BIE general assembly is composed of delegates appointed by the member states and can range between one to three representatives. However, each nation has one vote in the general assembly.

Voting could take up to three hours and will comprise of three secret ballots, the Dubai Media Office said. The candidate with the least amount of votes will be eliminated after each round.

But if a candidate gets two thirds of all votes by the 168 member nations of the BIE in the first or second ballot, that country will be announced the winner immediately, the media office added.

The UAE too has been focused on its final presentation.

Describing it as the last opportunity for candidate cities to make their case to the voting nations, the media office said that the higher committee for hosting Expo 2020 had reviewed preparations for the presentation.

On Tuesday, the BIE general assembly will work on commission reports and review progress on other exhibitions such as the Expo Milano 2015, the International Horticultural Expo Antalya 2016 and Expo Astana 2017.