Shortly after dusk one evening next week a small group of people will light candles amid the bustle and noise of one of London's busiest road junctions, by King's Cross station. Their quiet ceremony will mark the deaths of 16 cyclists in the capital so far during 2011 – up from 10 the previous year – and demand measures to make cycling safer, particularly on such chaotic, lorry-choked intersections.

Among their number will be Debbie Dorling, whose husband, Brian, died eight weeks ago riding around a similarly notorious junction, at Bow roundabout in east London, after a collision with a lorry. The 58-year-old was a hugely experienced cyclist who commuted up to 200 miles each week to his job at the Olympic park.

"He knew all about the perils of lorries, and the perils of roundabouts," Debbie said. "The solution should be to segregate cyclists from the rest of the traffic. Bicycles and HGVs don't mix. Something has to be done, quite clearly."

There are fears that London's experience is being reflected elsewhere around Britain. In the first half of this year the number of cyclists killed or seriously hurt on UK roads rose 12% year-on-year. Other government data shows road casualties declining consistently over recent decades for all types of transport – except one. For cyclists, these numbers hit a low in 2004 and have since started to creep up.

Campaigners stress that much of this is accounted for by cycling's increased popularity over recent years, and that overall the pursuit remains very safe and statistically far more likely to increase a rider's lifespan through better fitness. But some remain concerned, blaming a variety of factors including a lack of cohesive central government policy on cycling infrastructure, too many lorries in busy urban areas and even the government's rhetoric on ending the "war on the motorist".

"It is a very worrying trend," said Chris Peck, policy co-ordinator for national cycle campaign group the CTC. "What we'll be asking the government for is a proper cycle safety action plan. There's really been no movement on this at all.

"Ultimately we don't know what's caused the increase in casualties. But in part it could be because we're allowing quite a lot of bad driving to go unpunished, which has simply led to a lowering of standards. There's no pressure on police to rigorously enforce speed limits, particularly lower limits, and we know the government's view on speed cameras."

A significant cycle safety focus is lorries, particularly in central London. Heavy good vehicles make up 5% of the city's traffic but are estimated to be involved in half of all cycling fatalities. It is also a concern elsewhere – last month a medical student died in Wythenshawe, Manchester, after his bike was crushed by a lorry.

"There's two key problems: there's dangerous junctions and there's lorries," said Mike Cavenett of the London Cycling Campaign (LCC), which is organising next week's vigil. "Even with one or the other you can get fatalities, but when you combine them especially so. You only have to look at the locations where there have been fatalities this year – this is not a surprise to anyone, why this is happening."

While the LCC blames Transport for London and the city's mayor, Boris Johnson, for neglecting cyclist safety – a charge they vigorously deny – national groups say ministers in Westminster have similarly little appetite to tackle the issue.

"Very clearly, the government hasn't got a coherent and effective road safety strategy that safeguards cyclists," said Jason Torrance, policy director for Sustrans, which campaigns for cycling and other sustainable travel. "One of the things that we hear, time and time again, is that cyclists want safe or segregated routes and that the speed and volume of traffic is a real concern and a real threat."

One issue is the lack of a single voice for cycling issues in government after Cycling England was abolished in April in the "bonfire of the quangos".

"We were telling government all the ways they could improve cycling and make it safer," said Phillip Darnton, the organisation's former chairman. "The trouble is that some of them are politically sensitive and you have to have a very clear, bold strategy. We did try to tread that careful line of saying, this is a considered opinion of all of the voices of cycling. And now it's terribly piecemeal."

The Department for Transport says it does take the issue seriously, citing spending such as £11m on Bikeability cycle training. Mike Penning, the road safety minister, said: "We take the issue of cycle safety extremely seriously and are working to reduce the instances of deaths and serious injuries of cyclists on our roads. The year-on-year rise in the number of cycle casualties may be due to the increase in cycling we have seen in recent years, but we will continue to monitor these figures closely."

Female cyclists

As a road safety trend it was both mysterious and particularly grisly: why were so many young female cyclists being killed by lorries?

The alarm was raised in 2009 in London, when of 13 riders killed around the city over the year, 10 were women, with eight of these involved in collisions with good vehicles, mainly construction trucks.

The apparently counter-intuitive theory that emerged was that one factor could be a perceived tendency among female riders to be more cautious on the roads. By hugging the kerb and not pedalling furiously to keep up with traffic they placed themselves at greater risk of being overtaken by trucks turning left when the cyclist was in their blind spot.

A number of high-profile incidents this year have involved women, including the death of Min Joo Lee, a 24-year-old fashion student crushed by a lorry outside King's Cross station. But most cycle campaigners call 2009 a statistical quirk – so far this year, overall, six of 16 cyclists killed in the city were women.

Chris Peck, from cycle campaign group the CTC, says the perception that young women are at particular risk comes in part from the fact that there deaths simply tend to get more press coverage. He said: "It sound terrible to say so, but that is part of it – it makes a better story."