Why can Russia sell petroleum only to settle in US dollars?

Russia is a big country exported to oil. Petroleum income is an important source of Russian income. However, if the international market always uses the US dollar to settle, there is a great risk, because the settlement of settlement is in the hands of the United States. , But I have to use the dollar, why is this?
It I think there are these factors:

1. Russia's ruble exchange rate fluctuates large, and the more important point is that rubles are not international circulation currency
To settle in importing countries, there must be rubles in the hands of the other country, but the ruble is not strong enough and non -international currency. Where can the general countries store it?
but to settlement, you must use the currency recognized by both parties, and both parties can accept both sides. Although Russia does not like the US dollar, there is no way to provide better and more credit currency. Settlement.

2, in addition to the US dollar, there are also currencies such as euro, yen, and pounds. Theoretically, it can be used for oil settlement, but the US dollar-oil system has been operated for decades and has been very mature.
and the euro area proposed to use the euro to buy oil. The specific landing system is far from perfect, and other currencies need not be said.
The comparison, there is really no other better choice, only the US dollar to settle.
3, the oil-the US dollar system is the foundation of the US financial hegemony. It will not let the country use other currencies to replace their status
. Since the disintegration of the Bretton forest system, the United States has been decoupled with gold, and Americans have been there. Looking for a "anchor" of the dollar, this "anchor" must be an indispensable large cargo for all countries, and eventually found oil.
If the United States and Opec ’s oil -producing countries reached an agreement. All countries that buy oil must be settled with US dollars to completely bundle oil with the US dollar. In this way, in addition to a very small number of oil -producing countries such as Iran and Russia, Other oil -producing countries only receive US dollars. This makes it impossible to leave the US dollar when buying and selling oil.

. So Russia does not want, but it is really at this stage. There is no way to get rid of the shadow of the US dollar to settle oil. How about it in the future, depending on whether it has the opportunity to find other alternative ways, such as the euro or RMB.

Because the US dollar is international currency, Russia holds more US dollars that can control the exchange rate of the US dollar and supplement national strength.

Because the dollar is strong!