There was an attempt to shoot down the helicopter of the President of Belarus

[Kurokage]

What Lukashenko says might be pure propaganda and nothing more.

​​​​​​However, he can be searching for a pretext to attack Ukraine. It's not a secret he's being pressured by Putin to join the war. So far he hesitated because he was afraid of potential riots at home if Belarusian soldiers started dying or if he announced mobilization. But nobody really knows what's going on in his head or what Putin promised him.

I doubt the Belarusian army is strong enough to occupy parts of Ukraine but opening a new front would distract Ukrainians' attention and further weaken the defense of the Eastern front.

Thats very true, but you also have to start thinking of a widening conflict dragging in surrounding countries that don't want to be under the Putin boot if Belarus is seen to be helping. I do think Lukashenko is worried about his position and by looking like he's not involved, he can try to stay ahead of any revolt in his own country when Putin falls.