Uranium seized from a suspected group of traffickers in the ex-Soviet state of Moldova will be sent to Germany to pinpoint its origin and degree of enrichment, officials said on Thursday.

Authorities in Moldova said this week they had seized almost two kilogrammes (around four pounds) of the radioactive substance Uranium-238 from a suspected group of traffickers, including former interior ministry officials.

"The Uranium-238 found in Moldova will be sent to the nuclear research centre in Germany for the identification of a producer country and the degree of enrichment of the radioactive substance," interior ministry spokesman Chiril Motpan told AFP.

"Talks with German experts are currently under way," he said, adding however it was still unclear how much of the substance would be sent. Moldova does not have laboratories to conduct the required analysis itself, he said.

Motpan reiterated the seized uranium was under guard, saying the operation to capture the radioactive matter lasted over a month.

"The country has not yet seen such a special operation before," he said. "It was the first time that contraband radioactive materials were intercepted in Moldova."

The suspected traffickers had wanted to sell the uranium for nine million euros (11 million dollars).

Experts have repeatedly expressed fears over traffickers obtaining nuclear materials from the former Soviet Union with the aim of selling them on to rogue groups in the hope of making the so-called dirty bomb.

The United States said Wednesday it gave technical assistance to Moldovan authorities over the seizure of the uranium.

Uranium-238 can be converted to create plutonium -- a source for nuclear power and nuclear warheads.