He said he would ensure that any steps taken would "not inflict damage on civil society in Russia".

His comments came a day after the lower house of parliament gave preliminary backing to a bill that would tighten controls on such foreign-funded groups.

Mr Putin said he would discuss the bill with parliamentary leaders.

NGOs protest

Mr Putin insisted that "political activity in Russia must be transparent to the maximum extent" and "the same applies to all issues related to the financing of political activities".

He was speaking to a top Kremlin human rights adviser, Ella Pamfilova, Russian media reported.

"The continuing funding of political activities in Russia from abroad must stay within the range of the government's attention. The more so if it is financed through state channels of other countries," he said.

In a 370-18 vote, the State Duma approved in the first reading the bill that would require all NGOs to re-register with a state commission.

The bill's sponsors say the aim is to prevent money-laundering and improve financial oversight.

NGOs say it will significantly curb their activities.

More than 1,000 NGOs have been urging the house to reject the bill.

Ukraine concerns

It is clear that the Kremlin is determined to crack down on politically active NGOs who receive foreign money, for fear they might help foment a Ukrainian-style revolution in Russia, the BBC's Emma Simpson reports from Moscow.

Procedurally, the bill will have to go for further readings in the Duma and will require presidential signature to become law.

Some 1,300 NGOs on Tuesday issued a statement that said the bill "hinders the development of civil society" in Russia.

The statement said that the proposed legislation would particularly target human rights organisations.

Lawyers for the big foreign groups - like Human Rights Watch - believe international organisations will no longer be able to have branch offices in Russia, our correspondent says.

Instead, they would have to register as independent Russian legal entities, a condition that many NGOs will find difficult to meet, she says.