Cristiano Ronaldo is in Portugal's preliminary squad for next month's Nations League matches, opening the door to an international return after his fallout with coach Jorge Jesus, a federation source told AFP.

The 41-year-old abruptly left the Portugal camp on September 30 during the opening qualifiers for the Nations League, before accusing Jesus of breaking his word about giving him game time.

A spokesperson for the Portuguese football federation (FPF) confirmed reports Ronaldo was in line for a return to the squad ahead of games at home to Denmark and in Wales on November 14 and 17.

Jesus will announce his final squad on November 6, the spokesperson added.

The FPF last week announced it had handed Ronaldo a 30-day suspension for walking out. The suspension was backdated, meaning he will be free to return by the end of this week.

Ronaldo apologised to supporters earlier in October, adding he would accept any punishment that was imposed.

In a social media post shortly after deserting his teammates, he accused Jesus of promising to give him playing time against Norway before failing to honour it but insisted he was not retiring from international duty.

He said a further bone of contention between him and the coach was Jesus had not mentioned at a press conference prior to the game with Denmark a series of points they had agreed upon.

Reigning champions Portugal won all four of their Nations League matches, three of them without Ronaldo, and qualified for the quarter-finals with two games to spare.

The five-time Ballon d'Or winner is the all-time top goalscorer and record appearance-maker in men's international football.

Ronaldo, who made his Portugal debut in 2003 at the age of 18, has said this will "probably" be his final year in football.