istanbul turkey sign letter intent france italy wednesday strengthen cooperation joint defense project include air missile defense systems turkish defense ministry source say first step franco-italian eurosam consortium turkish company look system base samp-t missile system produce eurosam determine common need three countries source say nato member turkey say plan buy russian s-400 surface-to-air missiles decision see western capitals snub alliance give tensions moscow ukraine syria russian deal also raise concern weapons integrate nato defense deal consummate s-400s turkey speak u.s. air force general tod walters head nato ally air command tell reuters berlin say would continue press turkish air force officials buy weapons could work together nato systems s-400 could obviously systems region possess capability demonstrate high high degree interoperability wolters say raytheon build patriot missile defense system also put offer turkey choose s-400 turkey continue talk eurosam consortium come second tender nato secretary-general jens stoltenberg last month say turkish president tayyip erdogan tell ankara discuss buy air defense systems france italy addition s-400s defense ministry source say turkey france italy would strengthen cooperation joint production military electronic systems software simulation systems warfare equipments well air missile defense systems letter intent sign brussels turkey defence minister nurettin canikli attend meet nato defense minister turkey france italy strengthen cooperation missile defense source