I found: https://www.eclipse.org/forums/index.php/t/1083627/ and on that basis I tried to add “-Dtycho.disableP2Mirrors=true” to the MAVEN_OPTS.
export MAVEN_OPTS="-Xmx1g -Dtycho.disableP2Mirrors=true"
This seems to have avoided the problem with the repository and my maven build works now.