The video shows a German woman hostage and her son pleading for help as their Iraqi kidnappers threatened to execute them unless Berlin withdraws its troops from Afghanistan.

Hannelore Krause, 61, and her 20-year-old son Sinan were sobbing and visibly distraught in the video picked up by the US-based SITE Institute which monitors Islamist websites.

Their captors extended by 10 days the deadline for Germany to withdraw its troops from Afghanistan or see the hostages executed, although the exact date of the new deadline was not immediately clear.

"It is really very difficult to watch how these people are humiliated on video," foreign ministry spokesman Martin Jäger told a press briefing.

He said ministry staff had studied the video overnight. "Many of us did not sleep much last night. We will be meeting with the ministry's crisis team this afternoon to give our interpretation of the video and try to draw final conclusions about it," Jäger said.

Hostage negotiators continue work

Germany's Foreign Minister Frank-Walter Steinmeier called the video "shocking and inhumane" adding that "all hope had not been lost" thanks to the crisis team which he said was working on winning the release of the pair.

Krause, who is married to an Iraqi doctor, and her son were seized on February 6 in Baghdad where they have lived for several years.

"I beg you, help me... I'm so afraid and we only have a few days left," Krause said in the video, crying as she and her son sat in front of a green wall rug in the video that SITE said was posted on the al-Hesbah Internet forum.

"I'm completely at the end of my rope. I'm a complete mess," said Krause, wearing a headscarf and black robes.

Apparently addressing her husband, Krause said: "You know that I would so much love to come home. I miss you so much. Please find some way (to help)."

SITE said the five-minute and 27-second video was produced by an Iraqi group called "Kataeb Siham al-Haq (Righteous Arrows Battalions)" that had threatened on March 10 to kill the Germans.

The group is seeking the withdrawal of German and Austrian forces from Afghanistan. SITE said the video extended the ultimatum for the withdrawal by 10 days.

Germany has nearly 3,000 troops in Afghanistan serving with the NATO-led force and Austria has a token contingent of around five officers.

Krause warned in the video that a failure to comply with her captors' demands would have consequences for both countries and her and her son.

A first deadline for the pair's execution came and went on March 20 with the German government unable to contact the kidnappers, German television reported at the time.

Berlin has made several appeals for the hostages' release including a message from German President Horst Köhler, contained in a video distributed in Germany and the Arab world, urging the kidnappers "to return the hostages to their family."

Chancellor Angela Merkel warned after meeting Afghan President Hamid Karzai last month that Germany would not be blackmailed into withdrawing its troops from Afghanistan.

Previous German hostages in Iraq have been released unharmed.

Kidnappers want attention

Terrorism expert Rolf Tophoven said the new video is a way to pressure the German government to give into demands.

"The goal of the hostage-takers is clearly to increase pressure on the Federal government," Tophoven said.

The video was made at the same time German Tornado fighter jets are being sent to Afghanistan. This shows that the kidnappers are informed about politics and are using it to their advantage, Tophoven said.

"The timing is striking," he said. "The kidnappers know the political situation in Germany. They also know that the government isn't able to be blackmailed," Tophoven said.

The kidnappers must also realize that it's unrealistic to demand Germany pull out of Afghanistan, the expert said, adding he thought it was a way for the kidnappers to up the ante, but that behind the scenes, the kidnapping is about money.

Terrorism expert Guido Steinberg agreed that the kidnappers likely want money.

"I don't really think that right now in Baghdad people are actually interested about what is happening in Afghanistan and that German troops are there," Steinberg said in a Wednesday morning interview with the German public broadcaster ARD.

Steinberg, a specialist on Islamist terrorism, said he was not suggesting that negotiators dismiss the link to Afghanistan. Kidnappers often make political demands as ways to get money.

"From my point of view, this is an attempt to use public opinion here in Germany to get attention and force the German government to follow the wishes of the German public," Steinberg said in the ARD interview.

If the kidnappers are actually trying to get money, the scare tactics will likely continue, Tophoven predicted. The new video does provide some hope for the hostages, since it shows that they haven't been killed and there is room for negotiation.