Opposition leader Adrian Delia hit out at third-country nationals, saying if the country had to bring in foreign workers, "they should at least be from the European Union".

Speaking at the General Workers’ Union conference Thursday morning, Dr Delia hit out at government plans to bring in 50,000 foreigners to work.

Prime Minister Joseph Muscat conceded there were challenges with the large influx of workers, but said the country would not push the pause button on its economic growth.

"There are certain issues we need to negotiate with the European Union," Dr Delia said. "Are we making enough effort to see that, if we do need workers, they come from the European Union," Dr Delia asked.

He also urged the government to introduce more family-friendly measures, noting the Nationalist Party was trying to increase the number of days off for fathers in the European Parliament.

Dr Delia urged workers to spend time with their family, urging them not to sacrifice their personal commitments for work.

The country was already sacrificing air quality and traffic infrastructure for work and construction, he insisted.