A group of eight locally engaged staff at the Spanish Consulate-General in Sydney walked off the job last month after bureaucrats in Madrid refused to pass on a 3.3 per cent pay increase, ordered by the Fair Work Commission as an increase to Australia's minimum wage.

The striking workers say pay rates vary between the Spanish government's diplomatic missions in Australia and have called on the Spanish Ambassador to Australia, Manuel Cacho Quesada, to intervene. The Spanish government's political and budgetary difficulties have prevented any pay rise for diplomatic officials in nine years.

Spain has one of Europe's largest budget deficits and has faced months of political malaise from inconclusive national elections.

The workers, who are permanent residents in Australia, met with the director of the Department of Foreign Affairs and Trade's Sydney office, Rhonda Piggott, this week to ask for help.

Some services at the Consulate-General are being halted as a result of the strike.

Only emergency assistance and fast-tracked passport applications are being processed.

Spain's main public sector union, the CSIF, has lodged a formal complaint with the Ministry of Foreign Affairs, while similar strikes are in place at Spain's embassy in Argentina, as well as at embassies, consulates and trade commissions in North America and Europe.

A representative of the group, who asked not to be named because he was not authorised to speak to the media, said they were seeking negotiations to bring wages and conditions into line with the Australian public service.

"Our salaries before taxes are not reasonable," he said.

"It's not what the market is offering for similar positions, given we are professionals and speak two or more languages.

"We tried over a year ago to contact the Spanish Minister of Foreign Affairs to seek a proper salary for Australian standards but it was ignored."

Calls for comment to the embassy in Canberra were not returned on Wednesday.