By William Mauldin 

The U.S. on Friday expanded its Russia sanctions to include a motorcycle group favored by Russian President Vladimir Putin as well as individuals and entities linked to the pro-Russian separatist movement in Ukraine.

The Treasury Department added 24 individuals and entities to a list that bars travel and bans financial contacts with U.S.-connected people and businesses. The new sanctions show the U.S. is ready to put further pressure on Russia, even after a collapse in the value of the ruble earlier this week.

The U.S. also is imposing, for the first time, a broad ban on doing business in the breakaway Crimea region. The move shows Washington is digging in for a prolonged standoff over the status of the region and seeking to make it an investment pariah.

The nationalist "Night Wolves" biker group was among those sanctioned. The group has frequently hosted Mr. Putin and its leader, Alexander Zaldostanov, known as the "Surgeon." The Treasury Department said Night Wolves members served in an armed group against the Ukrainian government and helped storm a natural-gas distribution station and the Naval headquarters in Sevastopol.

Others hit by the new sanctions include officials in the Donetsk People's Republic, the main separatist entity in the eastern Ukraine city of Donetsk; Konstantin Malofeev, blamed for financing separatists in Crimea; and Mr. Malofeev's investment group, Marshall Capital Fund.

Representatives of Marshall Capital and Night Wolves couldn't immediately be reached for comment.

"These actions target people who are undermining peace and stability in Ukraine and impose additional costs on Russia for its destabilizing actions," said David Cohen, the Treasury's undersecretary for terrorism and financial intelligence.

The measures roughly coincide with the European Union's sanctions announced Thursday on Crimea-based companies.

Russia's foreign ministry denounced the EU measures, calling them "nothing but an attempt to punish the people living on the [Crimean] peninsula who made their free choice at the referendum and decided to reunite with Russia."

Canada also added sanctions on Friday, imposing restrictions on exports of energy technology and products, including steel pipes used in pipelines, rock-drilling tools, drilling derricks and production platforms.

"Canada will not accept the illegal occupation of Crimea and persistent, provocative military activity in eastern Ukraine," Prime Minister Stephen Harper said, warning that his country stands ready to take further measures together with allies and partners if required.

Nirmala Menon contributed to this article