Japan and Fiji are being considered as potential partners to join New Zealand, South Africa, Australia and Argentina in the Rugby Championship, according to reports from the UK.

The Times is reporting that last weekend's meeting between the SANZAAR unions in Tokyo were successful and they've agreed in principle to expand the southern hemisphere tournament to include Japan.

There has also been talks to include a Pacific Island nation, with Fiji emerging as the most likely contender.

The report adds SANZAAR will take the process further forward on Friday when they sit down to discuss expansion directly with Japan.

World Rugby vice-chairman Agustin Pichot has also been working with SANZAAR to get Japan included.

In June, World Rugby abandoned plans for a Nations Championship, which would have given Fiji, Japan and other national teams the chance to take on more top sides.