British PM David Cameron has conceded that the thousands of Syrian “moderate rebels” allegedly ready to fight Islamic State include “relatively hard line Islamist groups,” joking that they were not the people one meets at a “Liberal Democrat conference.”

Cameron was grilled by MPs on the UK’s role in the Syrian crisis, with questions raised concerning the background of the so-called moderate groups in Syria, which the British government is supporting on the ground and the PM has been claiming number in the tens of thousands.

Cameron admitted to a committee of senior MPs that there were not enough “moderate rebels” overall, adding that some of them actually were “relatively hardline Islamists.”

“Some of the opposition forces are Islamist. Some of them are relatively hardline Islamist,” Cameron told the Liaison committee. “They are not all the sort of people you would bump into at a Liberal Democrat party conference.”

West’s airstrikes cost ‘billions’ to Syria economy – Damascus’ UN envoy https://t.co/ggQkMiGO0upic.twitter.com/xPoGbvgWrv — RT (@RT_com) January 12, 2016

Cameron added that the “deep tensions” between Iran and Saudi Arabia are not helping the peace negotiations in Syria and making it “incredibly difficult” to end the civil war.

The UK will continue to persuade moderate opposition groups to attend the next round of talks on January 25 – the date set for rebels to sit down with representatives of Bashar Assad’s regime to discuss a ceasefire agreement.

RT’s Eisa Ali pointed out that Cameron is still refusing to identify which groups these supposedly moderate “70,000 rebels” belong to.

To the question: “Why won’t you or the Defense Secretary name the supposedly moderate groups in whose name these fighters are in the field?” Cameron responded: “We’ll be effectively giving President Assad a list of the groups and the people and potentially the areas he should be targeting.”

READ MORE: Russian air force provides support for 7,000 Syrian rebels advancing on ISIS – General Staff

In reality, however, these “moderate rebel groups” have their own social media accounts, where they name the areas where they are fighting, Ali reported.

Cameron also said that he cannot “envisage a situation in which Assad stays in power and Syria isn’t a threat to our national interest.”

Meanwhile on Tuesday, Russian President Vladimir Putin told Germany’s Bild that Russia supports Syrian President Bashar Assad’s forces, but will back anti-Assad rebels as long as they are fighting Islamic State (IS, formerly ISIS/ISIL).

“We support both Assad’s army and the armed opposition,” Putin said in a lengthy recent interview to the newspaper, now published in full. “Some of them have publicly declared this, others prefer to remain silent, but the work is ongoing.”

A report released in December by the Centre on Religion & Geopolitics, a think-tank run by the Tony Blair Faith Foundation, warned that the West is making a strategic error in focusing its anti-terrorist efforts on IS, but overlooking other groups.

Sixty percent of the fighters in the country can be classified as Islamists that have similar goals to those of Islamic State, the report says. Those fighters belong to at least 15 other militant groups, which are mostly being ignored by the West.

READ MORE: 65,000 jihadists in Syria ready to replace ISIS if it’s defeated – report