Trade union Solidarity lodged a complaint with the United Nations on Tuesday against the South African government for allegedly not complying with a resolution regarding racism.

"In it, the UN is requested to exhort the South African government about non-compliance with procedural requirements of the UN convention on... [the elimination of racial discrimination]," it said in a statement.

The complaint was brought to the UN's committee on the elimination of all forms of racial discrimination (Cerd).

Solidarity said government had to report on its efforts to comply with the convention every two years.

"However, the South African government last submitted a report in 2006," the union claimed.

Government spokesman Donald Liphoko said: "We are aware that Solidarity is engaging with the United Nations. It is a matter that government is taking seriously."

He said government would provide further comment later.

Solidarity said a similar complaint would be lodged with the SA Human Rights Commission (SAHRC), appointed by government to act as a watchdog on behalf of Cerd in South Africa.

"Solidarity is requesting the SAHRC to exhort government about its non-compliance with the resolution and, should government still fail to comply, to file an application before the high court in terms of the powers vested in the SAHRC by which to compel government to fulfil its statutory duty."

Once government was ready to submit its reports, the union would submit its own "shadow report".

Solidarity chief executive Dirk Hermann said its prima facie case was that South Africa did not comply with international requirements and that the country was guilty of unfair racial discrimination.

"South Africa, however, makes it very difficult to make international comparisons if government never submits reports," Hermann said in the statement.