WASHINGTON -- US President Barack Obama intends to sign into law a bill that will ratchet up sanctions on Russia and provide additional assistance to Ukraine, the White House said on Tuesday.

At a regular briefing, White House spokesman Josh Earnest expressed the administration's concerns about the legislation because "it includes some sanctions language that does not reflect the consultations that are ongoing."

"That said, because it does preserve the president's flexibility to carry out the strategy, he does intend to sign the bill," Earnest said, adding that he anticipated Obama would sign the bill before the end of the week.

The Ukraine Freedom Support Act, which passed both houses of the Congress last week, requires Obama to apply sanctions against Russian defense firms, including specifically Rosoboronexport, a state-owned arms dealer. It would also target Russia's energy companies.

In addition, the bill would give Obama the authority to provide $350-million-US dollar military assistance to Ukraine. It includes anti-tank and anti-armor weapons.

Russian Deputy Foreign Minister Sergei Ryabkov said on Saturday that the new US legislation testified to "the anti-Russian sentiments as well as attempts to impose decisions on us that are categorically unacceptable."

The new legislation comes as the value of Russia's currency, the ruble, has collapsed in recent weeks and the price of oil, Russia's top export, experienced a large drop.

The United States and Europe have levied several rounds of penalties on Russia's energy, financial and military sectors over its alleged destabilizing role in the Ukraine crisis, seriously hitting Russia's economy as the most recent official report said the country will fall into recession in 2015.