Danes went to the polls on Thursday to vote in a referendum over whether to stay within the European cross-border security agency Europol. The ballot, the first on EU rules in 15 years, has been seen a test of whether or not Denmark wishes to further integrate into the European Union.

When the EU as it now stands was beginning to form in the early 1990s, Britain, Ireland and Denmark were all granted certain concessions for their participation in the now 28-member bloc. This meant exemptions from specific laws concerning EU justice and home affairs.

Prime Minister Lars Lokke Rasmussen's right-wing Liberal party alongside its main opposition, the Social Democrats, have encouraged voters to choose "Yes" and replace the current opt-out system with one in which Denmark could decide on a case-by-case basis whether to work with Europol.

"A 'Yes' is the safe choice. It ensures that we remain in Europol and can cooperate against crime," said Rasmussen , adding that "when we talk about cross-border crime like drug smuggling or human trafficking, we can't solve it alone in little Denmark."

But the far-right populist Danish People's Party, which now represents the second-largest group in parliament, was vehemently supporting the "No" campaign, saying giving up their exemption would be tantamount to handing over national sovereignty to Brussels.

Danes undecided as Britain looks on

Surveys show that Danes are split nearly evenly with a large percentage undecided, illustrating how great public uncertainly remains over the issue.

"I think it's important we don't give up our sovereignty," 25-year-old "No" voter Lea Sommer Holmberg told German news agency DPA. "It's important power stays with the people so politicians cannot just do what they want."

"Yes" voter Steen Boring, however, told DPA he thought it was important to cast a ballot in the positive because "we are a small country, we need some bigger friends."

The poll is being watched closely by British politicians, where a 2017 referendum on remaining in the EU is planned. Should "No" win the day, Prime Minister David Cameron could use it to show how other nations are discontent with the current state of the EU as he tries to renegotiate terms of membership.

es/jm (dpa, Reuters)