Hundreds of Israelis gathered near parliament on Thursday to smoke cannabis in an act of defiance of current laws.

Sitting in small groups on mats shaded by trees in the Rose Garden just across from the Knesset, participants lit up as the clock struck 4:20 pm for the local version of the traditional worldwide April 20 pro-cannabis events, known as "420" rallies.

In the afternoon, revellers were mostly men in their early 20s but organisers expected thousands more people to join the event, set to continue until the early hours of Friday.

Police did not intervene.

Israelis pass around a marijuana joint in Jerusalem on April 20, 2017 during a rally at the Rose garden, to celebrate 420 and to express their defiance of current laws (AFP)

To Itamar Yitzhakov, nearly 22 years old from Holon near Tel Aviv, the smoking event - known locally as the Big Bong Night - was already "a tradition."

"Once a year we celebrate cannabis day. We forget all our troubles, gather here - all the brothers who smoke - and we bond," he said.

Yitzhakov said he has been smoking for a few years but he only came out of the "cannabis closet" to his parents and employers a few months ago.

"I don't smoke huge quantities," he said. "After a hard day's work, I want to roll myself a nice joint."

Last month, the government approved a plan partially decriminalising cannabis use in public in favour of fines and treatment, but cannabis advocates are calling for full legalisation.

'I like to smoke'

The Big Bong Nights were founded by Amos Dov Silver, a legalisation activist who organised the first such event in 2014 and a second one in 2016.

Silver was imprisoned for his role in the 2014 event, following which he left Israel for California where he has been living for the past 18 months.

Speaking with AFP from his American exile, Silver said the event was not a demonstration or a protest as much as it was a way to challenge the authorities' mindset on cannabis by bringing together thousands of smokers at once, whose numbers would be too great for the police to hand everyone a ticket.

"The more people present, the more the awareness will rise and we'll be able to start advancing legalisation," Yitzhakov said as he held a smoking mango-scented joint.

Legalisation might take time, but decriminalisation was welcomed by Tal Ofer - "43 years old, a father to a 16-month-old child, totally normative, employed as a programmer - and I like to smoke," he said.

An Israeli smokes a marijuana joint in Jerusalem on April 20, 2017 during a rally at the Rose garden, to celebrate 420 and to express their defiance of current laws (AFP)

Ofer, from Gan Yavne, near the southern coastal city of Ashdod, who brought his non-smoking wife and baby to the event, described it as "a physical act of totally peaceful protest" pertaining to his personal liberties.

"I want to smoke. I know it's good for me. I know how good the material is," he said.

As a "very hyperactive person," for Ofer smoking cannabis was mainly a way to calm himself down and enable him to focus.

"This is my healthy Ritalin," he said, referring to a drug for treating attention deficit hyperactivity disorder.

While Ofer acknowledged the legal and procedural complexities of full-fledged legalisation, Yitzhakov was undeterred in his hopes it would happen soon. 

"I believe there will be legalisation this year. It's always good to hope - what harm can it do?"

The code 420 is most often used in North America, attributed to a group of young cannabis users in the 1970s who met up at 4.20pm.