The Spanish government has begun slapping embargoes on some clubs' future earnings as it tries to force them to settle outstanding tax bills worth around €750 million at the start of the year.

The clubs' liabilities attracted the attention of European Union anti-trust officials, prompting the government and the football league (LFP) to agree a "road map" in April designed to allow them to settle up.

Spain's tax agency has collected €329.9m this year, with €305m coming from clubs in the First Division, according to an agency briefing note.

Some €130m more is expected to pour into the agency's coffers this year, around €55m of which is accounted for by embargoes placed on income from sources including audiovisual rights, ticket sales and lottery, the note said.

The agency declined to specify which clubs had been affected by the embargoes.