As border tensions rise, Belarus refuses to commit soldiers to Ukraine until attacked.

(CNN) ⸻ Belarusian President Alexander Lukashenko has claimed that his country will not send troops into Ukraine unless it is attacked. He has close ties with Russian President Vladimir Putin, and the Kremlin's spokesperson, Dmitry Peskov, has announced that Putin will meet with Lukashenko in the Moscow region on Friday. Belarus helped Russia launch its initial invasion of Ukraine last February, allowing the Kremlin's troops to enter the country through the 1,000-kilometer (621-mile) Ukrainian-Belarusian border. Minsk has since claimed that Ukrainian drones and missiles have entered its territory, sometimes without providing evidence. Tensions have been mounting at the border again in recent days as Ukraine braces for a renewed attack. A CNN team visited Belarus's southwest border near northwest Ukraine earlier this week, accompanied by state border officials, and saw the Belarusian government's fortification of the border area with barbed wire. The Ukrainian side of the border is heavily barricaded with several layers of barbed wire and earth mounds to stop anyone from going through. Belarusian officials told CNN that the border crossing from their side in the small town of Dyvin is still functioning, but that the Ukrainian side has closed the crossing. Kyiv has closed all border crossings to Belarus, except to occasionally allow entry to Ukrainian refugees who are looking to return to their home country, out of concern Belarus could be used for a further invasion by Russia. Russian troops launched the invasion on February 24, crossing into Ukraine from Belarus after months amassing along Ukraine's border. Belarus remains one of Russia's closest allies and has played a key role in its invasion of Ukraine. The two nations have engaged in joint military drills near the Belarus-Ukraine crossing.