MADRID (Reuters) - About 25,000 Ukrainians have arrived in Spain since Russia launched its invasion on Feb. 24, though only 9,000 of them have registered so far with the authorities, Spanish Migration Minister Jose Luis Escriva said on Monday.

       The United Nations refugee agency estimates nearly 3.5 million Ukrainians have now fled their country, with more than two million of them moving to neighbouring Poland. Romania, Hungary and Slovakia also host large numbers of refugees.

       In Spain, which is far from the conflict, many of the Ukrainians who have arrived are staying with relatives or friends and have not yet notified the authorities, Escriva said.

       "We have expanded the granting of residence permits to include all people who lived in Ukraine at the time of the invasion, not just Ukrainians," Escriva said in an interview with Spanish public news channel TVE.

       Escriva said he expects around 9,000 more refugees to register with Spanish authorities this week and to receive European Union temporary protection orders allowing them to immediately obtain residence and work permits in the country.

       Ukrainians can freely enter the EU without a visa but require residency permits to remain.

       (Reporting by Christina Thykjaer, editing by Inti Landauro and Gareth Jones)