"We are very clear that in the end, if needed, we are willing to go to court. But of course we are hoping these companies will be moving by themselves," De Rijk told Reuters in an interview.
"We are willing to engage in talks, but we are in a hurry as well, so we won't accept talks for the sake of talks themselves," he said. "Climate science is very clear. This is exactly what is needed."
Shell is appealing against The Hague district court order to cut emissions in line with the 2015 Paris agreement.
Among leaders in finance, retailers, oil and energy majors, builders and industrial manufacturers on the list are KLM, the Dutch arm of airline Air France KLM, ABN Amro bank ABNd.AS and supermarket operator Ahold Delhaize.
"You lead an enterprise with control over and influence on a substantial amount of CO2 emissions. An enterprise that can and must contribute to the system change necessary to prevent dangerous climate change," a draft letter seen by Reuters said, asking: "Are you a frontrunner or a straggler"
Some of the businesses are "small in the Netherlands itself, but they have a very large, international, global impact and the Shell verdict very clearly states that it is ...possible to hold them accountable for their global emissions via the Dutch law," he said.
The move by Milieudefensie follows a commitment by countries to accelerate their emissions reductions at the COP26 climate talks in Glasgow in November, with investors managing $130 trillion in assets signing up to net-zero and pressuring companies to ensure their plans are good enough.
The broadening out of Milieudefensie's campaign also comes against a backdrop of increased climate-related litigation globally, with more than 1,000 cases brought since 2015, research from the London School of Economics showed.
Milieudefensie set a three-month deadline until April 15 for the companies to present a climate plan. They will be used to set an emissions baseline against which progress in cutting climate-heating gasses can be measured, the group said.
Other companies receiving a letter were: Pension fund ABP, insurer Aegon, paint maker AkzoNobel, insurer Atradius, builder BAM Groep, dredger Boskalis Westminster, oil company BP, Dow Chemical, nutrition maker DSM, oil company ExxonMobil, dairy group FrieslandCampina, bank ING Groep, airline KLM, chemical manufacturer LyondellBasell, insurer NN Group, pension fund PfZW, Rabobank, energy company RWE, Schiphol airport, oil major Shell, car producer Stellantis, Tata Steel, products group Unilever, Uniper energy, food group Vion, commodities trader Vitol, Vopak storage and Yara chemical.
KLM said it has committed to aligning its net-zero pathway with climate science, and planned to use more sustainable aviation fuel.
An ABN spokesperson said the bank supported efforts to limit global warming and was working to reduce emissions from its lending.
Ahold Delhaize said it had not yet received the official letter and could not comment.
(Reporting by Anthony Deutsch in Amsterdam and Simon Jessop in London; Editing by William Maclean) ((firstname.lastname@example.org; +31202066563;))