Question: Is multipath routing supported for IPv6

I tried configuring multipath Ipv6 route using "iproute2" tool and it failed:

ip route add 143:2:3:4::/64 nexthop dev eth0

RTNETLINK answers: No such device

Same Command works for Ipv4. I looked into the source code and I don't
see support for RTA_MULTIPATH in IPV6 codebase.

I wonder if netlink configuration part is missing, or entire support
for multipath is missing. Is there any historical reason for not
supporting it?

Thanks
Mahesh