The banknotes proved too much of a temptation for the thieves

The work by artist Jan Christensen, entitled Relative Value, was made up of notes worth 100,000 kroner ($16,300, 12,400 euros).

The robbers got into the gallery by breaking a window.

They then cut each note off the canvas individually and left the 6.5-by-13ft (two-by-four-metre) frame behind.

The work had already been sold to a Norwegian buyer at face value.

"The piece was sold for nothing basically. It was just an exchange," Mr Christensen told the BBC News website.

"I wanted to make a blunt work with the intention of creating a discussion about the value of art, and about capitalism, and how the art world works," he said.

Mr Christensen said he did not know whether he would make a replacement.

The artist wanted to create a discussion about the value of art

"We were afraid something like this might happen," he said.

"I didn't want to compromise the artwork but I realised it might cause some problems."

The thieves managed to make off with the money despite security measures being in place when they broke in late on Sunday.

Mr Christensen believes that the presence in Oslo of many high-profile guests for the King of Norway's birthday celebrations had diverted many of the city's police from their usual duties.

Despite the double blow of losing an artwork made up of his own money, Mr Christensen says he finds the theft "interesting".

"It proves my theory that I have made an artwork that has a value outside the gallery space."

"It means a lot to me that the myth can continue," he said, referring to the fact that the notes could end up in general circulation.

He said he found it puzzling that someone might wish to risk jail for relatively small amount of money, and is unsure as to what type of person would have stolen his art.

"It could be a drug user, but at least it's one who's interested in art," he said.