Azerbaijan has angrily denied an Iranian claim that it has been helping Israeli spies plotting against Iran.
Iran says agents of the Israeli secret service Mossad were behind recent killings of Iranian nuclear scientists.
The latest victim was Mostafa Ahmadi-Roshan, killed by a car bomb in north Tehran on 11 January.
Azerbaijan’s foreign ministry called Iran’s claim “slander”. On Sunday Iran had summoned the Azeri ambassador and given him a protest note.
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