President George W. Bush on Monday moved to step up military co-operation with Turkey, in an attempt to dissuade Ankara from launching a large-scale incursion into northern Iraq to hunt down Kurdish rebels.

But it was unclear whether Mr Bush’s offer to deepen intelligence-sharing and establish a military liaison system would be enough to reduce domestic political pressure on Recep Tayyip Erdogan – the Turkish prime minister, on a visit to the US – to take decisive military action against PKK Kurdish separatists in Iraq.