Spain and Portugal will start an analysis of whether to bid for the 2030 World Cup, the countries' football federations said on Saturday.
They did not make any mention of Morocco, who were previously also said to have been involved.
"After holding several meetings, the football federations of Spain and Portugal can confirm that they are set to begin an in-depth analysis of the possibility of presenting a joint bid to host the 2030 World Cup," a joint statement said.
"Both federations would like to take this opportunity to state that the governments of both countries have been properly informed about this process, given that they will have a key part to play in its development."
Spain's acting Prime Minister, Pedro Sanchez, said during a visit to Morocco last year that he had suggested a three-way bid with the North African nation to stage the 48-team event.
The three federations could not immediately be reached for further comment.
Spain, the 2010 World Cup winners, hosted the 1982 tournament and launched a failed bid, along with Portugal, to stage the 2018 tournament, which was awarded to Russia.
Portugal has never hosted the World Cup but did hold the 2004 European Championship.
Morocco has made five failed bids to host the tournament, most recently for the 2026 event which was instead awarded to the United States, Mexico and Canada.
Argentina, Uruguay, Chile and Paraguay have announced they will make a four-way bid, which could have sentimental value as Uruguay hosted the inaugural World Cup in 1930.
England is carrying out a feasibility study along with Northern Ireland, Scotland and Wales, while Bulgaria, Serbia, Greece and Romania are also planning a joint bid.