Crude oil and the dollar strengthened as tensions rose in Ukraine.

Jake Sullivan, the White House national security adviser, said at a media briefing on Friday that Russia had amassed enough troops near Ukraine to launch an attack at any time, possibly with air strikes, and called on American citizens to leave Ukraine quickly within 24 to 48 hours.

Affected by the news, the March futures price of WTI crude oil rose 3.58% to US $93.10 per barrel, while the April futures price of Brent crude oil rose 3.31% to US $94.44 per barrel. Both rose 0.9 per cent and 1.3 per cent respectively last week, the highest levels of recent-month contracts since September 2014.

Oil prices have risen for the eighth week in a row. Ed Moya, senior market analyst for Oanda's Americas business, said: "the oil market has been waiting for an important catalyst to justify oil prices above $100, while the situation in Ukraine seems to be just beginning to deteriorate. He added that any expectation of a supply disruption could push oil prices up by another 10 per cent. The International Energy Agency (IEA) warned that signs of a decline in OPEC+ production were worsening, with production in January 900000 b / d below target.

In the most recent week, however, the number of oil rigs in the US surged by 19-the biggest weekly increase since the outbreak nearly two years ago-to a 22-month high of 516, which could help boost US crude oil production. Bank of America Corporation analysts also said that as nuclear talks resume in Vienna, the US and Iran are likely to make progress in reaching an agreement that "will change the rules of the game and could lead to a surplus in the global oil market".

At the same time, the dollar also strengthened. The dollar index, which measures the dollar's exchange rate against six major currencies, rose 0.258%, while the rouble fell 2.73% against the dollar.

Bipan Rai, head of foreign exchange strategy at CIBC Capital Markets in Toronto, said the dollar's strength was due to Sullivan's comments and reports of Russia's decision to invade Ukraine. He said the rise in the dollar, coupled with moves in other safe havens such as US Treasuries and the yen, showed growing concern about the prospect of an invasion.