PARIS (Reuters) -France has warned it may try to block some crypto firms licenced in other EU countries from operating domestically as part of a push to get oversight transferred to the bloc’s central securities regulator, the head of its financial watchdog told Reuters. France's securities watchdog, the AMF, is concerned that under the EU's new regulatory regime, crypto companies are seeking out jurisdictions with more lenient licensing standards, its president, Marie-Anne Barbat-Layani, said. MiCA, a landmark set of digital asset rules which came into force this year, allows crypto companies to apply for licences from individual EU members, which they can use as a "passport" to operate throughout the 27-nation bloc.