Dragonja, who was the economy minister in the previous government, was the government's chief advocate in parliament for changes at Luka Koper and came under attack after he listed at a June session of the parliamentary Public Finance Oversight Commission outdated data on Luka Koper's return on equity.

Cerar said that Dragonja had expressed his wish to withdraw on Tuesday and that he would accept the resignation. He is convinced that the two remaining state secretaries at the ministry would stay on and that "a competent person to replace Dragonja would be found very fast".

The development coincides with today's resignation of Finance Minister Dušan Mramor, who commented by saying he saw no professional reasons for Dragonja's decision.

"It is however true that the pressure was strong. Handling affairs related to state asset management is also very exposed politically," said Mramor, who said he was resigning for personal reasons in a move that seems unrelated to Dragonja's motives.

Dragonja used in parliament in mid June 2011-2013 data when the Koper port's return on equity was 2.5%, while it has increased to 15.4% since.

He accepted responsibility for the wrong data, saying he "made a mistake...but had no intention of manipulating the data and misleading the public". Speculation about his resignation already started at the end of June.

Dragonja appeared in parliament to advocate for plans by the Slovenian Sovereign Holding, the state assets custodian, to replace three Luka Koper's supervisors amid preparations for the construction of a second rail track to the port.

The board overhaul was eventually shelved due to strong resistance at the port, which escalated into a blockade lasting several days.