By Nicholas Vinocur
PARIS (Reuters) - French leftists and hardline trade unionists sought to derail President Francois Hollande's bid to reform the country's labour rules on Tuesday as the legislation making the changes entered the lower house of parliament.
The draft law aims to make it easier for companies to dismiss workers during a downturn and take other measures to loosen up French labour practices often criticised as too rigid.
Labour Minister Michel Sapin said Hollande's Socialist government was determined to pass the law, which was based on a deal struck in January between moderate unions and employers after months of strained negotiations.
Hollande says the reforms, which would also increase protection for temporary contract workers, are a vital part of his efforts to revitalise the economy and reduce unemployment stuck over 10 percent and growing.
But the Communist-backed CGT union, which did not sign the January 11 deal, is stepping up attacks on the proposed changes as it rallies supporters for street protests set for Apr. 5.
Left-wing lawmakers presented thousands of amendments to the law on Tuesday in a bid to stall its progress towards final legislation.
Hollande could force the bill through with his parliamentary majority. But a concerted street campaign conducted by a trade union that backed him to run for president last year would embarrass him, tarnish his left-wing credentials and possibly rob him of supporters ahead of future votes.
"This law is bad for all workers... We will do our best to make sure that it does not pass in parliament," Thierry Lepaon, leader of the CGT union, told France Inter radio.
Union and left-wing opponents have accused Hollande of abandoning his campaign promises and selling out Socialist principles to financial markets in his efforts to kick-start the economy.
The CGT has campaigned against the law at ailing factories across France where leaders denounced members of the CFDT - one of the moderate unions that signed the deal - as "collaborators" with the French national employers' federation, known as Medef.
Lawmakers in a left-wing coalition known as the Left Front, which has close ties to the CGT, are also campaigning and plan to present 4,500 amendments to parliament during the debate.
"Our objective is to have the entire text withdrawn," said Andre Chassaigne, a parliamentary spokesman for the group.
The law is also opposed by left-wing Socialists in Hollande's majority who are presenting 400 amendments to "rebalance" a bill they see too weighted in favour of employers.
Sapin has signalled he is ready to accept one of the amendments - a change to a clause that had originally given employers the ability to offer staff a choice between redundancy and relocation to another site. Any such pressure to relocate would clash with existing European labour law, he said.
The labour minister told RTL radio any change to the text would have to be verified by the signatory parties for a final vote by the end of April.
(Editing by Mark John and Andrew Heavens)