France already had 200 troops serving with UNIFIL, and President Chirac on Thursday promised to bolster that to 2,000.
His pledge came the day before EU foreign ministers were due to meet in Brussels to nail down troop offers from member states.
Italy may contribute up to 3,000 troops, and Spain 800.
Lebanese Prime Minister Fuad Siniora said on Friday that France's decision to enlarge its troop presence will bolster European participation and help consolidate stability in the country.
"Undoubtedly, the French decision will help boost European participation," Mr Siniora said in a statement.
"In turn, this will help speed up the formation of the international force, which along with the Lebanese army, will protect civilians and achieve security and stability," he said.
French troops welcomed
The latest contingent of 170 French troops arrived in the Mediterranean port of Naqura on Friday, from the French amphibious assault craft Foudre.
Several landing craft transported the soldiers and their trucks,
bulldozers, dump trucks, generators and water purification equipment ashore.
"This reassures me. The number of troops is not important, it's what they can do, if they can protect the Lebanese or not," said Ali Taher, as he watched from the rooftop of a nearby house.
"Israel always comes here, destroys everything, and burns everything. I don't want this anymore, we have the right to live. Why can Israeli and French people live in peace, but not the Lebanese?" asked the 47-year-old man.
The soldiers, specialists in de-mining and reconstruction, will be under the command of the United Nations Interim Force in Lebanon (UNIFIL), Admiral Xavier Magne told news agency AFP.
"They ... are basically preparing the ground for further deployments. Their role is to prepare for further deployment, check for landmines and prepare facilities for future troops," UNIFIL spokesman Alexander Ivanko said.
Asked about difficulties that might obstruct a smooth UN deployment, he said: "the Israelis are withdrawing, the ceasefire is holding well and there have been only minor incidents reported."
Colonel Christophe Issac, the commanding officer of the engineering detachment, told news agency AFP the mission of the soldiers will be to support the deployment of UNIFIL and Lebanese army forces in southern Lebanon.
He also said one of their main tasks will be to help clear landmines.
"The different protagonists left behind a certain amount of unexploded ordnance, whether unexploded bomblets, anti-personnel or anti-tank mines, or various explosive devices," he said.
The UN force is seen as crucial in shoring up a fragile ceasefire between Israel and the Lebanese Shiite militia Hezbollah that came into effect August 14 after more than a month of fierce fighting.
Under UN Security Council Resolution 1701, which ended the 34 days of fighting, the ineffectual UN force is to be expanded from about 2,000 to up to 15,000 troops to help monitor the ceasefire.
The deployment of the French troops "helps strengthen stability in Lebanon and allows the country to regain its territories through an Israeli withdrawal and the extension of state authority over all territories," he said.