Protesting farmers clogged roads around an EU summit taking place in Brussels on Thursday with around 1,000 tractors, a Belgian police said.
"There are 1,000 tractors or agricultural machinery" being kept away from the gathering of the European Union's 27 leaders, a police spokesman told AFP. He added that the farmers were mainly from Belgium.
They are protesting over tax, regulation, and an influx of produce from Ukraine as a consequence of the war.
French farmers also kept up roadblocks around Paris, making access to the capital difficult.
Truckloads of police backed up by armoured vehicles were controlling access early Thursday.
Another convoy of tractors heading for Rungis from southwest France was searching for a new route after being held up by police.
In a sign of the pressure on Paris, President Emmanuel Macron has scheduled a one-on-one interview with European Commission chief Ursula von der Leyen before an EU leaders' summit gets under way in Brussels later Thursday.
Macron's office said the two would discuss "the future of European agriculture", after more than a week of farmers' protests.
Initial gestures from the bloc have failed to calm demonstrations and road blockades that have dogged major agricultural powers, especially France.
- 'Fewer restrictions' -
They included a temporary exemption from rules requiring some farmland to be left fallow and limits to imports of some Ukrainian agricultural products, on which tariffs were dropped following Russia's 2022 invasion.
Paris hailed the moves as a victory for its lobbying of Brussels.
But they have not been enough to soothe the grievances of the farmers.
"We want fewer restrictions and especially to be able to fight on the same terms as our competitors," Nicolas Galopin, a farmer from south of Paris, told broadcaster France Inter as he manned a blockade on the A6 motorway.
"It always makes us sick to see more and more of our food being imported, to be dependent," he added.
Brussels has said a contentious free-trade deal with Latin American bloc Mercosur will not go ahead in its current state, although some farmers want it dropped altogether.
French and Belgian farmers had blocked a border crossing point together late Wednesday to condemn trade bargains they say "distort competition".
Away from Brussels, France's second-largest farmers' union Coordination Rurale (CR) suggested members gather at the National Assembly parliament building.
"Given that a lot of farmers want to come to Paris, we're telling them... go to the National Assembly, so that all the MPs and senators can come and meet the farmers," CR's president Veronique Le Floch told RMC radio.
She said members of the profession were heading to the capital in support of their "colleagues" arrested at Rungis on Wednesday.