Richard Nixon’s visit to Prague in October 1989 is still shrouded in mystery
The autumn of 1989 was eventful. One of them took place almost in secret: on Thursday, 12 October 1989, former US President Richard Nixon arrived in Prague. Was his visit really only private? State security, which had been monitoring Nixon’s stay in Czechoslovakia (though not in detail, as it later turned out), discovered that Erban had telephoned the playwright and leading Czechoslovak dissident Václav Havel after meeting Nixon – and invited him to visit.
Source : https://plus.rozhlas.cz/navsteva-richarda-nixona-v-praze-v-rijnu-1989-je-stale-zahalena-tajemstvim