The secret services of a NATO country is 'highly likely' to have been behind the assassination of ambassador Andrey Karlov, claimed a top ally of Vladimir Putin.

Senior senator Frantz Klintsevich, deputy chairman of the Russian upper chamber's defence and security committee, said: 'It was a planned action.

'Everyone knew that he was going to attend this photo exhibition.

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A key ally of Vladimir Putin, centre, has blamed NATO for the murder of the Russian Ambassador to Turkey Andrey Karlov, right, while attending an exhibition in Ankara

Ambassador Karlov, pictured here moments before his death, was killed by a police officer

The gunman, pictured, has been named as Mevlüt Mert Altıntaş, who was also shot dead

The claim on NATO involvement was made by Putin ally Franz Klintsevich, pictured

'It can be ISIS, or the Kurdish army which tries to hurt Erdogan.

'But may be - and it is highly likely - that representatives of foreign NATO secret services are behind it.

'What has happened is a true provocation, a challenge.

'It is a challenge for Russia.'

The senator is a member of the ruling council of United Russia party, Putin's vehicle of power.

The Russian Foreign Ministry vowed that terrorism would not win after the assassination of the Russian ambassador in Turkey.

Spokeswoman Maria Zakharova said: 'We call this event an act of terror.

'Terrorism will not win.

'We will strongly fight it.'

Political consultant Dmitry Fetisov warned: 'There is no doubt a reaction will follow, both for Syrian terrorists and for Turkish power.

'Our position in Syria will become tougher, surely.

'No single country that respects itself can forgive such a cruel act as the murder of its own ambassador.

' It will make Russia angrier.

'It will throw all its military forces at eliminating the nest of Syria's terrorists.'

A family friend of the dead envoy said he came from a family of Soviet-era diplomats.

'He was a brave and risky man, but our secret services should have warned him,' said

Pogos Akopov, ex-USSR ambassador to Libya, who served with Karlov's father.

'Our security services, and theirs (Turkey's) are to blame.'

Senior pro-Putin senator Alexei Pushkov claimed: 'This murder is the consequence of attempts to blame Russia for all the sins and the crimes it did not commit.'

The Western media gave a 'distorted and false' image of what is happening in Aleppo and this 'contributed to this terrorist act'.

He warned: 'This is a result of anti-Russian hysteria, raised in the West and supported by a certain part of Turkish society.

'This should be a serious signal to the Turkish authorities so that they come to the conclusion that it is time to stop a tantrum.

'The problem in Syria is that there is needed to find the ways to neutralise the militants and go to the political process, rather than to support of psychological tension to the situation in that country.'

He warned: 'Those who planned and carried out this terrorist act, of course, were planning to attack the Russian-Turkish relations.

'The murder of ambassador is an unprecedented event, it is one of the darkest chapters in the history of bilateral relations.