We address the question how sensitive international knowledge flows respond to geo-political conflicts taking the politico-economic tensions between EU-Russia since the Ukraine crisis 2014 as case study. We base our econometric analysis on comprehensive data covering more than 500 million scientific publications and 8 million international co-publications between 1995 and 2018. Our findings indicate that the imposition of EU sanctions and Russian counter-sanctions from 2014 onwards has significa...