According to an initial estimation submitted to the government in February 2015, construction of the eastern border was to cost €79 million. Based on recently completed construction projects, however, the total cost is expected to increase by €118 million to €197 million, the ministry said.

Anvelt confirmed that construction on the border will continue as in previous years, and work planned for the current year will move forward as well. "Estonia will be getting the best eastern border possible, which likewise constitutes the external border of the EU and NATO, and no concessions will be made in that regard," he confirmed. "But the current situation will definitely have to be discussed in the government."

The minister has launched an internal audit in order to determine how the border construction project was drawn up and why the project was delayed.

"The audit must determine whether mistakes were made in the planning of the construction of the eastern border, whether calculations were based on objective data, and why the difference in cost is so large," said Anvelt, who wants clear answers before proceeding with naming the next director general of the PPA.

PPA: Difficult conditions, Natura 2000 sites

According to PPA director general Elmar Vaher, some of the main issues that have driven up the projected cost of the border project include difficult natural conditions, swampy areas, requirements for Natura 2000 sites, and high surface water levels and the need to redirect said water.

The technological solutions needed for border surveillance will end up costing more than initially projected as well.

"Since beginning the development [of the border project], the PPA has informed its partners that the final cost of constructing the border will be determined after its planning," Vaher explained, adding that such a large-scale construction can only be budgeted after various studies are completed, including construction and technical studies and an IT project.