The US is closely following reports of the arrest of Indian opposition figure Arvind Kejriwal and encourages a fair legal process, a State Department spokesperson said on Monday after Germany's reaction to the case sparked a protest from India.

Kejriwal, a national opposition figure and chief minister of Delhi's capital territory, was arrested by India's financial crime-fighting agency on Thursday on corruption charges that his political party rejects, a month before national elections.

"We encourage a fair, transparent, and timely legal process for Chief Minister Kejriwal," the US spokesperson said in response to an emailed query about the case, in which India summoned a German envoy on Saturday to protest against his government's remarks about the arrest.

Asked about the arrest at a government press conference on Friday, Sebastian Fischer, spokesperson for Germany's foreign office said that like anyone else facing accusations, Kejriwal was entitled to a fair and impartial trial.

"We assume and expect that the standards relating to independence of judiciary and basic democratic principles will also be applied in this case," he said.

New Delhi summoned the German embassy's deputy chief of mission, Georg Enzweiler, "and conveyed India’s strong protest," at the remarks, India's foreign ministry said on Saturday.

"We see such remarks as interfering in our judicial process and undermining the independence of our judiciary," it said in a statement. "Biased assumptions made on this account are most unwarranted."

Asked about India's protest to Germany, the State Department spokesperson said: "We would refer you to the German Foreign Ministry for comment on their discussions with the Indian government."

Washington has increasingly come to see India as an important strategic and economic partner in its effort to push back against China's growing power worldwide.

Indian Prime Minister Narendra Modi's government has frequently shown itself sensitive to human rights criticism, and rights advocates have accused U.S. President Joe Biden's administration of putting strategic considerations above such issues in its dealings with New Delhi.

New Delhi and Berlin also share good ties, and the two countries have been coming closer on strategic issues, including defense technology.

India's government and Modi's Hindu nationalist Bharatiya Janata Party deny any political interference in the case involving Kejriwal and other leaders of his Aam Aadmi Party.

India's Washington embassy did not immediately respond to a request for comment on the State Department's reaction.