Why can't I delete this remote bookmark in Mercurial (hg)?

Why can't I delete this remote bookmark in Mercurial (hg)?

I read that I could delete a remote bookmark foo using
hg book -d foo
hg push -B foo
Please tell me what I'm doing wrong here, while trying to delete the
bookmark @default locally (which works) and then remotely (which doesn't
work, so it gets restored again on next pull):
$ hg pull
pulling from /tmp/foo/base
searching for changes
no changes found
divergent bookmark @ stored as @default
$ hg book
* @ 8:d7a82de9f7c9
@default 9:c12daad73af2
$ hg book -d @default
$ hg book
* @ 8:d7a82de9f7c9
$ hg push -B @default
pushing to /tmp/foo/base
searching for changes
no changes found
bookmark @default does not exist on the local or remote repository!
$ hg in -B
comparing with /tmp/foo/base
searching for changed bookmarks
no changed bookmarks found
$ hg out -B
comparing with /tmp/foo/base
searching for changed bookmarks
no changed bookmarks found
$ hg pull
pulling from /tmp/foo/base
searching for changes
no changes found
divergent bookmark @ stored as @default
$ hg book
* @ 8:d7a82de9f7c9
@default 9:c12daad73af2
Thanks!