Rugby's governing body say that the rescheduling of the games in June and July will provide "certainty for the union, players and fans and allow them maximum preparation time in advance of the matches".

The rescheduling has been deemed necessary to maximise time following the conclusion of the review into the 2017-2018 Rugby Europe Championship.

Russia have received a late call up for the World Cup in Japan following the review, which saw Spain, Romania and Belgium thrown out of the qualifying event for fielding ineligible players.

Subject to any appeal, the winner of the European play-off between Germany and Portugal, which is provisionally scheduled for June 9, will play Samoa in home and away matches to determine the final place at the World Cup.

The first leg will take place in the Samoan capital of Apia on June 30 with the return leg in Europe on July 14.

The winner over the two legs will join Ireland, Scotland, Japan and Russia in Pool A in Japan.

The loser could still qualify as they will take part in the repechage competition in November.

"The rescheduled dates will enable the least-possible disruption for Samoa's European and Southern Hemisphere based players, who will be released under regulation nine, which covers all Rugby World Cup qualifiers," a World Rugby statement said.

"It also enables all qualifiers to be completed prior to the repechage competition."

World Rugby have also announced that they are funding Samoa's entry into the 2018 World Rugby Pacific Nations Cup in Fiji, which takes place from June 9 to 16.