US Vice President Joe Biden will meet Turkish President Recep Tayyip Erdogan today aiming to ease strains over the crisis in Syria and persuade Turkey to step up its support for the coalition against Islamic State (IS) jihadists.
The trip to Istanbul by Biden, the highest ranking US official to visit Turkey since Erdogan won election as president after over a decade as prime minister, comes amid unusual tensions in the traditionally strong relationship between the two NATO allies.
Washington is frustrated by the relatively limited role played by Turkey in the fight against IS jihadists who have seized swathes of Iraq and Syria right up to the Turkish border.
Turkey in turn is upset that its contribution in hosting 1.6 million refugees from the Syrian conflict has gone relatively unrecognised and is wary of supporting the Kurdish fighters battling IS.
Biden personally stung Erdogan last month by suggesting his policies in supporting Islamist rebel forces in Syria had helped encourage the rise of IS, a slight that prompted the president to warn his relationship with the US number two could be "history".
But the straight-talking Biden said after arriving in Istanbul that openness was a key part of the US-Turkey relationship.
"Friends don't let the other wonder about what they are thinking," said Biden.
Biden is due to meet Erdogan on the shores of the Bosphorus on Saturday afternoon.
In talks late Friday with Prime Minister Ahmet Davutoglu, Biden agreed on the need to "degrade and defeat IS" as well as work to a "political transition" in Syria, the US administration said, without giving further details.
So far, Turkey's sole contribution to the coalition has been allowing a contingent of Iraqi peshmerga Kurdish fighters to transit Turkish soil to fight IS militants for control of the Syrian border town of Kobane.
The government has also so far refused to allow US forces to stage bombing raids from the Incirlik air base in southern Turkey, forcing them to make far longer sorties from the Gulf.
