Spy poisoning: why Putin may have engineered gruesome calling card

Insiders say all trails lead back to Moscow, suggesting a deliberate act to incite row with UKThe response from the Kremlin has been uncompromising. The foreign ministry described Theresa May’s accusation against Moscow as a “circus show”. Its boss Sergei Lavrov said there was no proof the poison used against Sergei Skripal came from Russia. And the embassy in London promised an “equal and opposite reaction” to any UK measures. Beneath this bluster, however, is cool