The two proposed amendements, sent out for consultation on 7 July, aim to cut red tape on employers and workers, the government said.
The first enables managers, executives and others who 'can determine the length of their own working hours' to work extra hours above their contract stipulation voluntarily without falling foul of the 48-hour-a-week legal limit.
The second removes the requirement on employers to keep detailed records for those who decide to opt out of the working time limits.
The TUC is also angry about what it sees as 'a wholly inadequate period of consultation of 10 days'. It said the amendments meant many white-collar workers would be excluded from the 48-hour limit by agreeing to 'voluntary' overtime.