Plans to declare an asylum crisis in the Netherlands were branded a “danger to democracy” by GroenLinks-PvdA leader Frans Timmermans on the opening day of the budget debate.

Timmermans said he would introduce a motion to block what he called an “undemocratic trick” designed to prevent the controversial plans being scrutinised by parliament.

PVV party leader Geert Wilders hit back at Timmermans, accusing him of “populism” and being “totally blind” to people’s concerns about migration. “You have a big fat zero when it comes to solutions,” Wilders said.

Timmermans said Wilders was trying to sideline parliament by using emergency powers to avoid a debate on measures such as freezing asylum applications and restricting refugees’ right to join their family members.

“If you want to know what we think about asylum and migration, set out your plans, I’ll talk to you about them day and night and then show you what we want,” he said.

“We’re not going to let people fall below the baseline, which is what you want. People are not packages that you can just chuck over the border.”

Letter to EU

Timmermans’s motion will almost certainly be voted down because the four coalition parties, who have a majority in parliament, included an asylum crisis law in the framework agreement that they signed in July.

Earlier in the day asylum minister Marjolein Faber sent an official letter to EU home affairs commissioner Ylva Johansson telling her the Dutch government would seek an opt-out from European migration and asylum rules “in case of treaty amendment”.

A spokesman for the EU appeared to pour cold water on the plan, pointing out that opt-outs required all 27 member states to agree to rewrite the treaties. “We don’t expect any immediate changes,” the spokesman said.

Timmermans has also come under pressure from members of his own party to take a harder line against the government on migration, after he said he was “always prepared to talk about how we can make asylum policy stricter and more basic, provided you keep within the law”.

More than 600 members of the GroenLinks and Labour (PvdA) parties, including councillors and officials, signed a letter distancing themselves from the comments, made in response to the king’s speech from the throne on Tuesday.

The asylum issue dominated the opening hours of Wednesday’s debate, with the coalition party leaders showing a united front against criticism from the opposition parties.

Raising VAT

Christian Democrat (CDA) leader Henri Bontenbal said it was “not OK to bypass parliament” and called for the government to use fast-track lawmaking mechanism rather than emergency powers.

Wilders denied that parliament was being bypassed and said MPs could repeal the measures. “It is a democratic route that has been passed by a majority of both houses, otherwise it wouldn’t be law,” he said.

Bontenbal and Timmermans, along with D66 leader Rob Jetten, also criticised the plan to raise VAT on sports club memberships, books and theatre tickets, which Jetten said was a tax on “all the pleasures of life”.

Wilders said the cabinet had already made concessions by compensating schools for the cost of textbooks.

Timmermans accused Wilders, who left the right-wing liberal VVD in 2006 to found his own party, of being a “radicalised VVD’er” who had ditched his election promises such as scrapping the excess charge on health insurance.

Health and Gaza

Wilders said the coalition had agreed to halve the excess from its current annual level of €385, calling it a necessary compromise.

The opposition were divided on the proposal, with Jetten, whose D66 party wanted to leave the payments untouched, arguing it would lead to higher insurance premiums and longer waiting lists.

The debate also featured clashes over the conflict in Gaza, with Timmermans accusing the cabinet of being “deaf to the fate of the Palestinians” during Israel’s bombardment of Gaza.

But Dilan Yesilgöz, leader of coalition party PVV, accused PvdD leader Esther Ouwehand of “dog-whistling” by serving watermelon slices ahead of the budget debate and posting images on social media. The red and green fruit with black pips has become a symbol of support for the Palestinian cause.

Ouwehand accused Yesilgöz of “fact-free rabble-rousing” by mentioning her gesture in the course of calling for the cabinet to take action on anti-Semitism.

Labour migrants

But in other areas the coalition leaders said they were willing to work with opposition parties to amend the cabinet’s plans.

Yesilgöz unexpectedly praised SP leader Jimmy Dijk after he said in an interview with NSC that all labour migrants should be required to learn Dutch, “funded by their employers.”

The VVD leader said she “absolutely saw scope” for working with the SP on the issue, though she stopped short of agreeing that employers should foot the bill. “I think we put together a very good agenda on this with the SP,” she said.

Wilders told Chris Stoffer, leader of the orthodox Protestant SGP, he was willing to do more to take in Christians seeking asylum from countries where they faced persecution.

“The image that the PVV never wants more asylum seekers is not true,” said Wilders, who during last year’s election debates called for the number to be cut to zero.

“If we can limit the numbers coming in, we can make room for those who need it,” he told Stoffer.