This year's Eurovision song contest, scheduled for May in Ukraine, has hit another road bump as the entire organizing team has resigned over allegations about lack of transparency in the preparation process.

"Hereby we, the Eurovision team, for whom this contest has become not only part of our work but also part of our life, officially inform that we are resigning and stopping work on preparations for the organization of the contest," reads an open letter, signed by 21 member of the Ukrainian Eurovision team.

The former team members complained that they were stripped of some major responsibilities last December when a new head of the organizing committee, Pavel Gritsak, was appointed and all attempts to achieve compromise led nowhere.

According to the letter, there was "lack of transparency in making decisions regarding key areas of operations," coupled with unresolved contractual issues with personnel and failure of tenders for subcontracting work related to the contest.

"In our opinion, all that gets in the way of high-quality and timely preparations for the contest in Ukraine," concluded the letter.

Among the organizing team members who resigned were executive producers Oleksandr Kharebin and Victoria Romanova, commercial director Iryna Asman, event manager Denys Bloshchynskyi and head of security Oleksii Karaban.

"The team have been instrumental in the planning for this year's Eurovision Song Contest, and we thank them for their hard work," the European Broadcasting Union (EBU), which runs Eurovision, said in a statement.

The EBU added that it had reiterated to the Ukrainian side "the importance of a speedy and efficient implementation of plans already agreed, despite staff changes."

The 2017 Eurovision Song Contest is set for May 9, 11 and 13. Ukraine won the right to host the contest thanks to the victory of its entrant, singer Jamala, in the last contest.

However, the preparations for the contest in the Ukrainian capital have been marred by controversies. Last year, the choice of the St. Sophia complex as a venue for the opening ceremony and the International Exhibition Center as the venue for the actual contest caused severe public criticism.

Later, Zurab Alasania, head of NTU, Ukraine's national TV and radio company, resigned amidst reports that the country was having troubles financing the song contest.

Still, Vyacheslav Kirillenko, Ukraine's deputy prime minister, was quoted by news agency TASS as saying that preparations for the contest are still going according to plan, and the resignation of the organizing team should not have a big impact.