The Rail, Maritime and Transport Workers union (RMT) and Aslef said they would ballot their members over a strike following a "serious breakdown in industrial relations" with London Underground.

Both groups will announce the result on February 9.

A spokesman for Aslef said the unions were considering a series of 24-hour stoppages.

They accuse London Underground of ignoring agreements, imposing change without negotiation and inflicting excessive punishments.

"Once again Tube management have jumped the gun and are trying to impose policies without agreement," RMT general secretary Bob Crow said in a statement.

"No doubt we will once more be accused of disruption but ... the blame once again lies squarely with management trying to impose rather than negotiate," Crow said.

A spokesman for London Underground said there was no justification for the ballot and that they were surprised by the move.

"We are committed to working with all our trade unions to resolve the issues they are raising through consultation and negotiation," he said.

The RMT staged two 24-hour strikes on the tube earlier in January following a row over work rosters but only a few stations were actually closed. A coordinated strike between the two unions could shut the entire network.