Extended notice is usually given when a sitting prime minister does not plan to seek re-election.
Politically, that is still a forbidden topic for the allies, and the foreign ministers are not planning to decide to change that, officials say.
The prime minister had planned to say:
Foreign ministers from the six countries are planning to meet to discuss Iran on Tuesday or Wednesday.
The minister also plans to attend.
The two ministers plan to talk in Italy next month at the annual meeting of the major industrialized nations, a Japanese Foreign Ministry official said.
Some predictions that ministers were planning to drop the threshold to £42.50 were confounded.
Already, he and his ministers plan for it.
Scandinavian ministers plan to dance around a maypole at midnight in a belated celebration of the summer solstice.
The two ministers also plan to meet in September in Madrid for what they termed "a frank and sincere dialogue."