Obama will leverage the political power of his office, when he makes the announcement in swing state Ohio, and argue that Chinese practices in the auto sector put US manufacturers at a disadvantage, a White House official said.

"The Obama Administration is launching an enforcement action against China at the World Trade Organization for illegally subsidizing exports in their autos and auto-parts sectors," a White House official said.

The official added, on condition of anonymity, that China's actions were "putting US auto parts manufacturers at a competitive disadvantage and that is encouraging the outsourcing of auto-parts production to China."

The announcement will be seen as highly political as Ohio is a critical state in the November 6 election, and the home for large numbers of workers in the auto industry and related auto parts sector.

Obama repeatedly touts his decision to offer the sickly US auto industry a government bailout in 2009 -- which Romney opposed -- as his campaign seeks to capture a state which is vital to the Republican's White House hopes.

The announcement represents something of a political trump card, following days of sparring between the two campaigns over the challenge posed by China's rise as an economic power, and the threat it has posed to the US economy.