Beaten diplomats and 'bad' tulips: Russian-Dutch ties get worse.

An assault on a top Dutch diplomat in his Moscow apartment could be just a random big-city crime, if possibly homophobic in nature. But the recent course of Russia-Netherlands relations suggests another explanation entirely.

Onno Elderenbosch, deputy chief of the Dutch mission in Moscow, was attacked by two men posing as electricians after he admitted them to his apartment Tuesday evening, according to Russian media reports. The intruders roughed him up, tied him to a chair, stole nothing but scrawled the term "LGBT" [lesbian, gay, bisexual, transgender] on his mirror in lipstick together with a Cupid's heart.

Writing on his Facebook page, Dutch Foreign Minister Frans Timmermans said he'd called in the Russian ambassador to the Netherlands for an explanation.

"Our people must be able to work [in Russia] safely and I want assurances that the Russian authorities also take their responsibility on that point," he wrote.

Russia responded Wednesday that Moscow police would try to find the culprits.

"Moscow expresses regret over the unfortunate incident on October 15, when the minister-counsellor of the embassy of the Netherlands in Moscow was beaten," Russia's Foreign Ministry said in a statement  Wednesday.

If the assault on Mr. Elderenbosch were an isolated incident, that would probably be the end of it. But it's just the latest in a downward spiral of Russo-Dutch acrimony that appears to be veering beyond normal diplomatic boundaries and turning the officially designated "Year of Russia-Netherlands Cooperation" into anything but.

Suspicious minds might read the attack on Elderenbosch as payback for an incident last week in which Dutch police erroneously arrested Dmitry Borodin, a Russian diplomat at The Hague, after neighbors filed a child-abuse complaint against him.

Russian media reports said that Borodin was beaten, handcuffed and hauled into a police station with his children, in violation of his diplomatic immunity.

An apology filed by the Dutch Foreign Ministry a week ago said that Mr. Borodin's diplomatic rights had been violated, but maintained that "the police officers concerned were acting in accordance with their professional responsibility in responding to a reported situation."

It's possible, for their part, that the Russians perceived Borodin's arrest and public humiliation as an unwarranted escalation of their bilateral row over the Dutch-flagged Greenpeace ship, the Arctic Sunrise, which was seized last month by Russian border guards in international waters – but inside Russia's zone of economic interest. Protesters from the ship were trying to post a protest banner on a giant Arctic drilling rig owned by the Russian state corporation Gazprom-Neft.

Russian nationalists, rallying in front of the Dutch Embassy in Moscow last weekend, insisted that the Dutch apology for Borodin's arrest was inadequate.

"We have the right to demand tougher measures against the lying Dutch officials. The interior minister should resign as his police officers conducted these acts, and so should do the foreign minister," the leader of the ultra-nationalist faction in Russia's parliament, Vladimir Zhirinovsky, was quoted as saying by the state-owned RIA-Novosti agency.

The Netherlands threatened to sue Russia for its "illegal" seizure of the Arctic Sunrise at the International Tribunal for the Law of the Sea, and sharply criticized Moscow for charging all 30 members of the ship's crew with piracy. Russia has blamed the Dutch government for failing to rein in Greenpeace's "illegal activities" in the Russian Arctic.

Amid this web of recrimination and retribution, there is another sure-fire sign that the spat between Russia and the Netherlands is serious and probably set to escalate.

Russia's official agricultural watchdog has suddenly discovered serious problems of "insect infestation" and other biological threats emanating from Holland's signature export, tulips. The market for Dutch flowers in Russia alone is estimated to be about $1 billion annually, and that could soon be shut down along with imports of Dutch dairy products, Russian officials are warning.

"You know it's a serious diplomatic dispute when our sanitary officials get involved and find problems with the produce of the targeted country," says Sergei Strokan, a foreign affairs columnist with the pro-business Moscow daily Kommersant.

"It's always framed as a scientific matter – nothing political you understand – but it always seems to involve countries we have diplomatic issues with and never ones we get along fine with. And the timing is always exquisite. Hence, we've had bans on Georgian wines and mineral waters, Moldovan wine, Latvian canned fish, Polish meat products, Belarussian cheese, and Ukrainian chocolates. And it always comes, coincidentally they insist, amid some sort of official row with that country," he says.

"You can tell an awful lot about Russian diplomacy by watching where our sanitary scientists point their microscopes. So, if it's the turn of Dutch tulips now, you know things are going very badly in the political relationship," he says.