Madrid will send six Eurofighter jets and 130 soldiers to Bulgaria between mid-November and early December to train local forces, the Spanish defence ministry said in a statement.

It added that a further deployment will see eight F18M fighter jets and 130 air force personnel sent to Romania between December and March 2023 as part of NATO's "reaction and deterrence" strategy.

A long-range aerial surveillance radar has also been deployed in Romania since October 17 and could remain until late June 2023, the statement said.

Spain will also increase its air force's missions forming part of an "aerial shield". The country has already sent 12 fighter jets to eastern NATO members Bulgaria, Lithuania and Estonia since Russia invaded its pro-Western neighbour in February.