TEHRAN, Iran — Iran confirmed Tuesday that it arrested two German nationals as they approached the home of a woman whose sentence of death-by-stoning on an adultery conviction has drawn international condemnation of Tehran.

Foreign Ministry spokesman Ramin Mehmanparast accused the two Germans of links to foreign-based Iranian groups trying to undermine Iran's clerical rulers, something that could signal future security-related charges. He did not identify them.

In Berlin, the German Journalists' Association said Monday that two German journalists were arrested Sunday while interviewing Sajjad Qaderzadeh, the son of the woman facing the stoning sentence, Sakineh Mohammadi Ashtiani. The union also did not name the journalists. The son apparently lives in his mother's home.

"Two Germans -- it is not clear whether they are journalists -- were arrested in Tabriz as they approached the home" of Ashtiani, Mehmanparast said. The 43-year-old mother of two is in prison in Tabriz, a provincial capital in northwestern Iran, waiting for the judiciary to decide her fate.

"Since they had links with foreign-based counterrevolutionary networks, they were arrested and the case is under review," the spokesman added. He said an Iranian anti-government group that "facilitated the interview is based in Germany." Many exiled Iranian opposition groups have offices in Germany.

The arrests will almost certainly elevate tensions between Iran and the West, already running high over suspicions about Tehran's nuclear ambitions.

Iran has also been holding two American men in prison for 14 months, adding to strains with the U.S. Tehran initially said the two crossed the border illegally from Iraq but later charged them with spying. The U.S. government and their families say the two were innocent hikers and if they strayed across the border, it was inadvertent.

Mehmanparast said it was up to Iran's powerful, hard-line judiciary to explain where the two are being held. The judiciary said Monday only that it arrested two foreigners who had entered the country on tourist visas and did not have documents to prove they were journalists.

Iran has temporarily suspended the controversial stoning verdict against Ashtiani under international pressure, but says no definite decision has yet been made about her case.

Ashtiani was first convicted in May 2006 of having an "illicit relationship" with two men following the death of her husband -- for which a court in Tabriz sentenced her to 99 lashes. Later that year she was also convicted of adultery, despite having retracted a confession, which she claims was made under duress. She was sentenced to death by stoning for the adultery conviction.