Uganda accused Rwanda on Friday of blocking goods trucks and other vehicles from entering the country, and of stopping its nationals from crossing into Uganda amid a resurgence of hostility between the two African neighbors.
Rwandan authorities have been blocking entry to vehicles from Uganda since Wednesday, Ugandan government spokesman Ofwono Opondo told reporters in Kampala, adding 129 cargo trucks were now stuck at the border.
Denying this, Rwandan Foreign Affairs Minister Richard Sezibera said trucks were being diverted to Kagitumba border crossing in the north because of construction at the busy Gatuna border post. "Those who have gone through Kagitumba, they have crossed," he said.
Sezibera said Rwanda was stopping its nationals from crossing the border because Rwandans going into Uganda have been detained and accused of being spies with no consular services provided to them.
"People are coming in, people are going out except for Rwandans who have been strongly advised not to travel to Uganda because of challenges of insecurity that they are facing there," he said. "It's not up to Rwanda. It's up to Uganda (to sort it out). Of course, Ugandans are welcome here, we have no problem on our side of the border."
Opondo said the crossing at Kagitumba was also blocked.
Ugandan officials had summoned Rwanda's ambassador to Uganda, Frank Mugambage, to provide an explanation, he said.
Speaking at a news conference before Sezibera's remarks, Opondo also denied that Rwandans were being held for political reasons, saying that if there were any Rwandans in Ugandan prisons they had been processed through the police and judicial system.
The dispute over border crossings appears to be an escalation of the Cold War-style hostilities and allegations by the two countries of supporting each other's dissidents that have been reported in Ugandan and regional media over recent months.
Opondo said Rwandans stopped at the border included traders and hundreds of children who cross the border daily to attend schools on the Ugandan side.
Landlocked Rwanda transports a significant amount of its imports via a trade route passing through Uganda from the Kenyan seaport of Mombasa.
The same trade route serves as a crucial pipeline for Kenyan exports and also helps supply merchandise to Burundi and parts of eastern Democratic Republic of Congo. A protracted halt to people and goods crossing any of the borders along the route has the potential to trigger a major regional economic crisis.
Relations between Rwanda and Uganda have historically alternated between friendly and hostile.
Rwandan President Paul Kagame was once a key figure in the rebel group that catapulted Ugandan leader Yoweri Museveni to power in 1986 and once served as a senior intelligence official in Uganda in the late 1980s. Later Museveni supported Kagame's rebel group that ended Rwanda's 1994 genocide.
But the two countries nearly went to war in the late 1990s after their forces clashed in neighboring Democratic Republic of Congo, where they jointly helped topple former dictator Mobutu Sese Seko before turning on each other.