What about the differences in moon-seeing which is nearly the same as the question of brother Khalyfah from Germany who started fasting according to Libya moon-seeing. What is your opinion in this regard, sheikh?

In the name of Allah, the All-Merciful, the Mercy-giving. There is a difference of opinion whether it is obligatory to fast Ramadan upon seeing the moon anywhere in the world or each country should observe its own moon-seeing as in hadith of Kuryb. This is a kind of agreeable difference of opinion.
Moreover, as the times of Prayers differ from one country to the other, there should be no problem over the different times of fasting. The crescent may appear to one country and disappear to the other if it sets before sunset. When the crescent sets before sunset, it is considered unborn at that time. But if all Muslims fast at the same moon-seeing, which is the position of the majority, there will be no problem.
What is important is that we have to depend on seeing it. In the Sunnah we read “Observer fasting when you see it [i.e. the new moon] and break your fast when you see it [again]” and “Do not observe fasting until you see the crescent.” This is a strong assertion from the lawgiver. Thus it must be seen actually. Those who depend on astronomical calculations have to depend on such calculations that prove the ability to see the crescent. However, if the calculations say that it will be there but it cannot be seen by naked eye, this cannot be relied on. Thus we rely on such calculations in negation not in affirmation because when the crescent is in a state of conjunction, which I call the period of sinking down, it is unborn though it has come to existence. Therefore, we say that people have to see it.