After the arbitration award was announced on 29 June, the European Commission said that it was willing to help to implement the ruling, which was declared by the Hague-based international tribunal.

Today the Commission said that Juncker had talked to the Slovenian and Croatian prime ministers and reiterated that the Commission "stands ready to contribute to or facilitate the process on how to best implement the arbitration award".

Prime Minister Miro Cerar welcomed Juncker's decision, saying that Timmermans was a "trustworthy person and a great expert in law, who could make a positive contribution".

"I welcome the decision of the European Commission to contribute to the process of implementation of the arbitration decision," Cerar told the press on the sidelines of a summit in Budapest.

He added that Slovenia was continuing dialogue with Croatia while also performing activities related to preparations to implement the ruling.

Cerar noted that parliament had passed today the relevant legislation and that Slovenia was also preparing "everything else that will be necessary".

The announcement comes three days after Cerar and Croatian Prime Minister Andrej Plenković were in Brussels for an Eastern Partnership Summit.

Cerar said after the event that he had talked to Plenković on the sidelines of the summit, adding that Juncker approached them and "said that the Commission was serious about the intervention it had offered".

"We'll see what the Commission's next step is. But definitely, this was stressed by Juncker, the intervention will go in the direction of arbitration ruling implementation, which needs to be achieved through dialogue," Cerar also said on Friday.

The Commission said today that Timmermans intends to travel to Slovenia and Croatia in order to discuss the matter before the end of the year.

The news from the Commission came just as Cerar and Plenković were both attending a summit of 16 Central and East European countries plus China in Budapest.

Speaking to the press before receiving the news of Juncker's decision, Cerar said that he had talked to Plenković at the sidelines of the meeting. The latter said in a separate statement that he expected Cerar to visit Zagreb before the end of the year.

Cerar said in his statement that there was a possibility for him to visit Croatia, however only if the country changes its position on border arbitration implementation.

But until now Slovenia received no guarantees that Croatia changed its decision not to uphold the arbitration tribunal's decision, said the prime minister.