One Cambodian soldier was killed on May 28 as troops exchanged fire in a disputed area known as the Emerald Triangle, where the borders of Cambodia, Thailand and Laos meet.

The Thai and Cambodian armies both said they acted in self-defense.

Thailand has imposed border restrictions with Cambodia in recent days, while Cambodia banned Thai dramas from TV and cinemas, closed a popular border checkpoint, and cut internet bandwidth from Thailand.

On Monday, Cambodia's influential former leader Hun Sen Monday issued an ultimatum to Thailand to lift border crossing restrictions within 24 hours or face a ban on all Thai fruit and vegetable imports.

Cambodian authorities said Tuesday their Thai counterparts still imposed the border restrictions, and Hun Sen's ultimatum took effect.

"We have implemented the ban on imports of Thai fruit and vegetables since this morning," Sok Veasna, director general of the General Department of Immigration, told AFP.

He said visitors could still cross the border between the two countries.

Cambodia has formally asked the International Court of Justice (ICJ) to help resolve the border dispute in four areas -- the site of last month's clash and three ancient temples.

Hun Sen said on Monday that his country had to go to the ICJ because Cambodia wanted "peace" as the two countries would never reach an agreement in the four areas.

Hun Sen also called on tens of thousands of Cambodian migrants working in Thailand to return home, saying they would face increasing discrimination as the border spat drags on.

The row dates back to the drawing of the countries' 800-kilometer frontier in the early 20th century during the French occupation of Indochina.

Cambodia has previously sought help from the ICJ in a territorial dispute over a border temple.

In 1962, the court ruled then the disputed Preah Vihear temple belonged to Cambodia and in 2013, the ICJ awarded an area next to the temple to Cambodia too. 

Thailand said it did not accept the court's jurisdiction.

Violence sparked by the dispute has led to 28 deaths in the region since 2008.