After several days of delays and uncertainty, the Baltic Performer, a blue cargo ship laden with bananas from Ecuador, finally docked under grey skies at the Helsingborg port in southern Sweden.

One of Sweden's two main unions for dockworkers, the Swedish Dockworkers Union, decided at the end of March that it would not unload vessels with ties to Russia, in protest against Moscow's invasion of Ukraine.

The 150-meter freighter, operated by a Swedish subsidiary of the Russian company Baltic Shipping, was one of the first ships affected by that decision.

"We're blocking all goods linked to Russia and the regime", Rolf Lyktoft, head of the local dockworkers' chapter, told AFP.

Ukrainian President Volodymyr Zelensky has called for Russian vessels to be blocked from the ports of the "free world".

On Tuesday, the EU executive proposed banning Russian ships from European ports.

So far, none of the 27 EU member states has instituted a national ban -- unlike Britain, which did so in early March.

Analysts say Europe has been wary to move on the issue due to a fear of Russian reprisals over its oil deliveries.

In Helsingborg, Lyktoft acknowledged that the decision taken by his 1,400 colleagues was largely symbolic, with only a small number of Russian-linked cargo ships passing through Sweden's ports.

But he hoped for a snowball effect.

"We hope that the International Dockworkers Council will decide to take the next step, with a worldwide decision to not touch Russian goods", he said.

Helsingborg port officials have kept a low profile. The Baltic Performer was ultimately quietly unloaded late Monday.

The ship had been scheduled to arrive at the port on Saturday evening, but had to postpone its arrival by a few days as there were no dockers willing to unload it.

The blockade imposed by the Swedish Dockers' Union includes Russian-flagged vessels, those owned by Russian companies but flying other flags, and those sailing to or from Russia.

Russian-owned freighters like the Baltic Performer may soon find themselves shut out of European ports
Russian-owned freighters like the Baltic Performer may soon find themselves shut out of European ports AFP / Camille BAS-WOHLERT

The Baltic Performer was unloaded by dockers from the Transport Workers' Union, Sweden's other main dockers union.

"We think they shouldn't have let the ship into the port, but the port authorities did," said head of that union, Tommy Wreeth.

Last week, his organisation also announced a blockade due to take effect on May 1 -- in order to give shipping companies time to make other arrangements.

According to Wreeth, 270 Russian-flagged vessels or with ties to Russia docked in EU ports in March, including four in Sweden.

Britain blocked Russian-linked ships from its ports in early March, although Russian cargo -- in particular oil -- is still able to enter on other ships for the time being.

Few initiatives have been taken elsewhere in Europe so far.

Before the EU proposal was announced on Tuesday, the CGT dockers union at France's second-biggest port Le Havre said any blockade decision had to "taken across Europe".

"Otherwise, the port of Le Havre or other French ports would be shooting themselves in the foot, with traffic just going to other ports that turn a blind eye", union representative Johan Fortier told AFP.

On March 3, the port of Hamburg suspended all loading and unloading of ships to and from Russia.

But "limited" operations resumed three weeks later, a spokesman told AFP, since "not all goods are on the EU sanctions list."

As in other European countries, German customs officials currently verify the contents of the containers and decide on a case-by-case basis.

EU ambassadors are to discuss the proposed ban at their meeting in Brussels on Wednesday. The proposal needs to be approved unanimously by all 27 member states.

If the EU introduces a blockade and Russia takes retaliatory measures against EU vessels, "this could significantly disrupt Russia's exports in the short-term", said Niels Rasmussen, chief analyst at shipowners' association Bimco.

However, "in the medium-term it is likely that non-Russia and non-EU ships would reposition into Russia-Europe", while the tankers hit by sanctions "would move into other markets", he told AFP.