Asselborn, who is on a one-day official visit to Slovenia, said at the joint press conference that European values and responsibility and solving possible problems in solidarity were "the ABC of the European Union".

The two ministers agreed that the relations between Slovenia and Luxembourg are very good, with the potential of further improvement, especially in business, as the countries share common interests and views at all levels.

Companies based in Luxembourg are actually the second-largest foreign investors in Slovenia, with the value of investments from Luxembourg in Slovenia increasing by a third last year.

Cerar and Asselborn also announced a new meeting of the foreign ministers and presidents of Belgium, the Netherlands and Luxembourg and Slovenia, either at the end of this year or in 2020.

The Slovenian foreign minister noted that the Benelux countries, ever since the Slovenian-Croatian border arbitration tribunal had issued its decision in 2017, had been supporting its respect and implementation.

Cerar expressed to his Luxembourgian counterpart Slovenia's concern over the growing number of illegal migrants crossing the Slovenian border from Croatia via the Western Balkan countries. He expects that measures will be taken to end this trend.

He also communicated Slovenia's concern over the continued checks on internal Schengen borders, which "undermine the spirit of cooperation", and the rumour that certain countries could enter the Schengen zone without meeting the required criteria, but he did not mention Croatia specifically.

Cerar thinks that the outgoing European Commission should not decide on Croatia's entry to the Schengen zone. If this happens, it would mean that there was indeed a political agreement between between Commission President Jean-Claude Juncker and Croatian PM Andrej Plenković, which would be completely unacceptable for Slovenia, he added.

According to him, what is the most important about the expansion of the Schengen zone is that it does not pose a security threat for the EU and Slovenia. Asselborn agreed, saying that meeting the criteria way the key for joining the zone.

The Luxembourgian foreign minister noted that two more countries, Bulgaria and Romania, were also waiting in line, but he could not give a personal assessment about whether Croatia met the criteria or which country was ready and which was not.

But Asselborn added that possible problems needed to be solved, and that the best way was by respecting rulings of international courts.

Cerar meanwhile said that Slovenia would communicate its arguments regarding the expansion of the Schengen zone at the level of the EU institutions.

It was also noted that both Slovenia and Luxembourg are strong advocates of the October session of the European Council confirming the invitation to North Macedonia and Albania for EU accession talks.

Cerar said that the EU must meet that commitment, and Asselborn reiterated that it was up to the EU to make the decision for the start of the talks, and that it should not miss the upcoming opportunity.

Slovenia and Luxembourg are also strong advocates of multilateralism, with Cerar stressing that great challenges, such as climate change, migration and terrorism could not be resolved by individual countries, but only with mutual cooperation.

Asselborn added that trans-Atlantic relations were important, and that US Donald Trump was not right when he spoke about patriotism instead of multilateralism.

Patriotism can easily turn into nationalism and Europe knows well where this can lead to, he said, adding that the EU must keep multilateralism also because no other region in the world did this.

Regarding migrations, he said that the EU was less prepared for a possible new crisis than in 2015, as it had failed to reform the Dublin Regulation, while solidarity within the union was declining. He called for a uniform migration policy and continued aid to Turkey, which is hosting 3.5 million of refugees.

Asselborn also noted that around 750 Slovenians lived and worked in Luxembourg, which was a lot for a country with around 600,000 people, adding that Slovenians contributed to the cultural diversity of the country.

The Luxembourgian FM, who last visited Slovenia in October 2017, was also received today by Prime Minister Marjan Šarec, President Borut Pahor, among others.