The Atlantic meridional overturning circulation (AMOC) is a key component of the global climate system. Many models predict a weakening or even a collapse of the AMOC under future climate change. Recent studies suggested a 20th century weakening of the AMOC of unprecedented amplitude ( 15%) over the last millennium. Here, we present δ18O of benthic foraminifera in a sediment core from the Laurentian Channel and demonstrate that the δ18O trend is linked to the strength of the AMOC. In this 100-year record, the AMOC signal decrease steadily to reach its minimum value in the late 1970’s. The weakest AMOC signal is constant until 2000. We present a longer δ18O record of 1,500 years and highlight the uniqueness of these high δ18O values over that period. Moreover, the long record is also characterized by statistically heavier δ18O during the Little Ice age suggesting a relatively weak AMOC.