Turkey may have reinforced its border controls on the Syrian frontier in recent months but the consequences of its previously laissez-faire attitude towards anti-Assad Islamist fighters are starting to catch up.

Confirmation of the three British teenage schoolgirls’ arrival in Syria after flying to Turkey last week showed that individuals intending to join the Islamic State in Iraq and the Levant (ISIS) are still able to cross the border with relative ease.

The BBC’s James Reynolds spoke to a people smuggler who told him how the girls were transported into Syria and how ISIS militants were able to receive new recruits at the Turkish border.

The three teenagers, Shamima Begum and Amira Abase, 15, and Kadiza Sultana, 16, travelled from London to Istanbul on 17th February. According to Turkish Deputy Prime Minister Bulent Arinc , the British authorities did not inform Turkey of their arrival in time. Insisting that Turkey should not be held responsible in any way, Mr Arinc claimed it was entirely the fault of the British side. “”It is a reprehensible act for Britain, a country famous for its Scotland Yard, to let the three girls leave Heathrow Airport for Istanbul and then let us know three days later,” Bulent Arinc said.

Scotland Yard has denied that they took three days to inform Turkey. The Metropolitan Police statement said they began working with Turkish authorities the day after the teenagers were reported missing. “Once we established that the girls had travelled to Turkey, police made contact with the foreign liaison officer at the Turkish Embassy in London on February 18th,” they said.

Prime Minister David Cameron has also denied Mr Arinc’s claim, telling Parliament what the Turkish deputy prime minister had said about a three-day delay was not accurate.

Nevertheless, British authorities acknowledge the need to review existing procedures and tighten arrangements on their borders. Prime Minister David Cameron has asked the home and transport secretaries to examine all the protocols they have in place.

In coming days, both Turkish diplomats and the national airline will be under the spotlight. The House of Commons home affairs select committee has invited the Turkish ambassador Abdurrahman Bilgic and Turkish Airlines chief executive Temel Kotil to give evidence on the 10th of March. The home affairs select committee chairman, Keith Vaz was critical of Turkish Airlines. He described at least four young and unaccompanied girls flying to Turkey on their way to reach ISIS without the airline alerting British authorities ass “shocking”.

According to a senior diplomatic source that I have spoken to, these select committee hearings where an ambassador is invited to give first-hand information are not that unusual. Two of Turkey’s most successful ambassadors in London, Ozdem Sanberk and Unal Cevikoz were able to put their governments’ views on highly contentious issues such as immigration, asylum and human trafficking in a clear and accurate way by appearing in these hearings.

It is very likely that Ambassador Bilgic will have a harder time to convince an increasingly sceptical cross-party group of British MPs. The UK has been one of the staunchest supporters of Turkey within the European Union but Turkey’s rapid slide into authoritarianism has been noted in London, both in government circles and, if the recent strongly-worded criticisms are anything to go by, in the British media.

Earlier this week, The Financial Times published a lead article titled “Turkey’s democracy on the path to a police state- Erdogan’s power grab is diminishing the global reputation of the country”. Commenting on President Erdogan’s transformation of Turkey into an authoritarian state by eroding democratic freedom and pluralism in the country, The Financial Times claimed this was damaging Turkey in several ways, including country’s international standing.

“As a nation of 77m situated at the crossroads between Europe and the Middle East, Turkey ought to be a strategic player at a time of profound upheaval in the Arab world. Instead, its foreign policy appears to be driven by the president’s personal whim. This has frayed Turkey’s ties with its neighbours. In particular, Mr Erdogan has seemed unpersuaded by the urgency of taking on the Islamic State in Iraq and the Levant — or Isis,” the FT said.

On Tuesday, Roger Boyes of the Times wrote : “Turkey must decide if it’s our friend or foe”. Claiming that Ankara has been playing NATO and ISIS off against each other in its quest for regional dominance, Mr Boyes commented that “Turkey has become such an ambiguous ally in the campaign against Islamic State that it may as well signpost its airport exits and motorways: “This Way to the Holy War.”

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