Access it from /proc file system.
cat /proc/net/arp
Result
P address HW type Flags HW address Mask Device 192.168.1.102 0x1 0x2 d0:16:b4:b9:23:92 * br0 192.168.1.10 0x1 0x2 18:e8:29:42:89:af * br0 192.168.1.1 0x1 0x2 00:e0:67:1f:ea:47 * br0 192.168.1.5 0x1 0x2 24:5e:be:27:76:59 * br0 192.168.1.2 0x1 0x2 44:a8:42:34:16:49 * br0 192.168.1.113 0x1 0x2 02:d8:61:ea:5b:a1 * br0 192.168.1.25 0x1 0x2 00:16:3e:13:ad:16 * br0 192.168.1.100 0x1 0x2 34:64:a9:61:c4:64 * br0 192.168.1.64 0x1 0x2 00:04:4b:5d:29:43 * br0 192.168.1.8 0x1 0x2 80:61:5f:05:e5:fa * br0 192.168.1.26 0x1 0x2 00:a0:98:7c:01:b3 * br0 192.168.1.41 0x1 0x2 ec:71:db:e7:81:f1 * br0