"For political reasons ... we're not firing anybody, we're not imposing any tax for another year, so what is the point for all this? The timing is suspicious, to put it mildly," Haddad said.
The federation's call is part of a drive by the Shia Hezbollah-led opposition to step up its protest campaign and topple the government.
"For political reasons ... we're not firing anybody, we're not imposing any tax for another year, so what is the point for all this? The timing is suspicious, to put it mildly"
Lebanese Minister for Economy and Trade
The government had announced economic plans to be presented to a Paris aid conference on January 25.
Beirut hopes that this will bring billions of dollars of aid to the economy, which was devastated by the war with Israel last summer.
The government plan includes tax reforms, raising value added tax (VAT), and the sale of all or part of its interests in the telecoms sector by the second quarter of this year.
The labour union opposes tax increases and privatisation efforts "that take away workers and employees' rights", according to Haddad.
"The labour unions are criticising taxes. I will say it once and twice and three times: no increases in taxes before 2008. So what are they moaning about?" Haddad said.
"Secondly, the programme aims to create thousands of jobs ... particularly in the telecom sector, so what is the point of striking and stopping work and paralysing the economy? Does it help workers, does it help the economy, and what does it achieve?
"Privatisation of the telecom sector will not result in any job losses at all ... I'm sure they [labour unions] want to work in the interest of labour and job creation."
Government initiatives intended to increase economic growth and ease the burden of Lebanon's public debt will be presented at the "Paris 3" conference on January 25.
On Sunday, the head of the anti-Syrian parliamentary majority in Lebanon accused Hezbollah of trying to sabotage the conference.
"It is very regrettable that Hezbollah, through its political leadership, media and finances ... should spearhead attacks against the Paris conference," Saad Hariri said in a statement.
"The conference has become a target for political sabotage from within (Lebanon) ... led and planned by those who should support it and ensure its success.
"This attack will not hit the government but will instead harm economic stability and the standard of living of the Lebanese people."
Hariri called for Lebanon to "unite around the noble objectives" of the conference".
Anti-government protesters have camped outside Siniora's offices in central Beirut since December 1 to try to force him to give up veto power to the opposition in a unity government or call an election.
Siniora, backed by the US and Saudi Arabia, has resisted the demands. The impasse has raised fears that the aid conference may be postponed or cancelled.
France's foreign minister has said international donors have not changed plans to help Lebanon, despite the political turmoil.
"We desperately need to go [to Paris] ... Postponement is not on the cards any more," Haddad said.