Paris police have city on lockdown as almost 150 world leaders gather
Major traffic restrictions forcing thousands of French motorists out of their cars were in place across Paris as police locked down the conference venue for the UN climate change summit.
Some 2,800 armed police were at the COP 21 (Conference of the Parties) site at Le Bourget north of the city, with only accredited delegates allowed enter the venue.
Police armed with sub-machine guns were also stationed overnight at hotels located near the venue, conducting security sweeps and keeping traffic moving.
The stringent measures were in place as almost 150 heads of state and government gathered for the first day of COP 21.
The French government said that "exceptional measures" were required following the Isil terrorist attacks on November 13 last which killed 130 people and injured hundreds.
While the conference will continue as planned, NGOs and civil society groups have expressed annoyance that a series of planned climate marches in the French capital were cancelled due to security measures in the French capital.
No taxis or private cars were allowed at the site on Sunday or yesterday, with motorways also closed.
Diversions were put in place, with motorists living outside Paris urged to leave for home earlier.
Public transport was available free of charge on both days.