Central bank director Klaas Knot, Pieter Hasekamp, director of the government’s macro-economic advisory unit CPB, and the finance ministry’s top civil servant Bas van den Dungen held talks with the four parties in talks on forming a new government on Tuesday.

They were brought on board to be briefed on the government’s financial situation and this, said RTL Nieuws, is a clear sign that the talks are now about more than just guarantees that all four parties will respect the rule of law.

The current talks – described by negotiator Ronald Plasterk – were meant as an intermediary stage to address VVD and NSC concerns about the anti-democratic policies put forward by the far right PVV.

Labour/GroenLinks leader Frans Timmermans and Esther Ouwehand from the pro-animal PvdD have now called on Plasterk to explain why the financial experts were brought in.

“The four parties are talking about policy without there being hard guarantees about the rule of law,” Timmermans said on social media. “That was not the deal and we need an explanation.”

Talks on forming a new coalition government started up in The Hague again on Tuesday, but the four party leaders gave little away about contents when questioned by reporters.

Plasterk too declined to comment on progress so far, pointing out that the four parties had agreed to keep “radio silence” to avoid leaks. That means nothing will be said about the process, the contents and the agenda, Plasterk said.

Last week the negotiators held three days of talks on a country estate but they are now back in The Hague and Plasterk is due to report back to parliament early next month. The talks were halted for two weeks over the Christmas break.