PARIS, Dec 13 (Reuters) - Media freedom group Reporters Sans Frontieres said on Thursday it was extremely concerned for a Ukrainian journalist kidnapped in Syria, as the deadline passed for a huge ransom demand from a group threatening to kill her.
Anhar Kochneva, who had been reporting for Russian media outlets in Syria, was taken hostage in October near Homs.
"Her kidnappers, allegedly members of the Free Syrian Army (FSA), have threatened to kill her tomorrow, Dec. 13 2012, if their demand for $50 million is not paid," a statement from the Paris-based RSF and three other groups said ahead of the deadline on Wednesday.
The groups called on the new Syrian National Coalition, which has close ties with the rebel FSA, to secure the release of the reporter immediately.
"We also call on the French, British and U.S. governments, as well as the European Union, to fully engage the National Coalition in compelling the FSA to facilitate Kochneva's release," the statement said.
It added that as those countries had recognised the coalition as the legitimate representatives of the Syrian people they bore a responsibility in highlighting to the coalition the need to respect human rights and condemn violations.
The coalition won recognition on Wednesday from "the Friends of Syria" group that opposes President Bashar al-Assad.
RSF said that Kochneva was known for criticising the Syrian opposition, which she had publicly accused of cruelty to civilians and prisoners.
In a statement on Wednesday, the Ukrainian Foreign Ministry said it was continuing dialogue with her captors and taking "all measures" to release her.
"Ukraine again expresses its deep concern over the situation around Anhar Kochneva who is illegally held in Syria by a group which calls itself a unit of the FSA," it said.
In video messages posted by her captors over the last two months, Kochneva has appealed to Ukraine and Russia to meet their demands.
In one video message dated Nov. 28 she reads out a statement in Arabic admitting she had been working as a military interpreter with Russian and Syrian officers.
"We are deeply concerned that in both video appeals the journalist seems to be speaking under pressure," RSF said.
Russia has shielded Assad's government from U.N. Security Council censure, resisting Western pressure to join efforts to push him from power, and has condemned the recognition of the new coalition by the United States and its allies.