Chancellor Angela Merkel's government was responding to a US demand made public a day earlier "to help secure" the world's busiest oil shipping lane and "combat Iranian aggression".

Merkel's spokeswoman Ulrike Demmer said Germany was "reluctant" to join such a US-led mission and had "not offered a contribution, as the overall approach of our policy toward Iran differs significantly from the current US approach".

Berlin was seeking an emphasis on "diplomacy and de-escalation", she said, as it also tries to save the Iran nuclear deal from which President Donald Trump withdrew last year.

Demmer said that "participation in a US-led mission could complicate this issue, even as of course we share the goal of freedom of navigation".

Foreign Minister Heiko Maas was even more direct, reflecting the position of his centre-left Social Democrats, who are junior coalition partners to Merkel's conservatives.

Germany "will not participate in the maritime mission proposed and planned by the US," said Maas, adding that "we are in close coordination with our French partners" on the issue.

Berlin "considers the US strategy of maximum pressure on Iran to be wrong," he said, speaking on a Warsaw visit.

Britain last week ordered its navy to escort UK-flagged ships in the strait in response to Iranian soldiers seizing a tanker in the flashpoint entrance to the Gulf.

Demmer said that Germany remained "in close coordination with France and Britain" on questions of maritime security, adding that Berlin believed the idea of a European naval mission was "worth considering".