Nearly half of all Danish voters are still uncertain how they will vote in the country's September referendum on the EU constitution, an opinion poll published Monday showed.

Of voters questioned in a Ramboell Management poll for Jyllands-Posten newspaper, 46 percent said they had not decided which way to vote, while 33 percent said they would vote for and 21 said they were against.

Some 52 percent of women said they were still undecided, against 39 percent of men.

The poll was carried out between March 7 and 10 among 996 people over 17 years of age.

"It is completely impossible to predict the outcome of the poll because many Danes will decide how to vote at the last minute," said Lars Bille, a political scientist at Copenhagen university.

The poll showed that 62 percent of those questioned said they were not well informed about the content of the proposed treaty.

A large majority of parties represented in the Danish parliament recommends a yes-vote in the September 27 referendum, with just the extreme right-wing Danish People's Party and the formerly communist Unity party rejecting the constitution.