NEW DELHI, March 3 (Reuters) - Russian Foreign Minister Sergei Lavrov accused the United States of hypocrisy after U.S. Secretary of State Antony Blinken said Russia cannot be allowed to wage war in Ukraine with impunity, during a security forum they attended in New Delhi on Friday.

The top diplomats from Moscow and Washington had both attended the Group of 20 foreign ministers gathering in the Indian capital earlier this week, and met in person for the first time since Russian forces invaded Ukraine a year ago.

"If we allow with impunity Russia to do what it's doing in Ukraine, then that’s a message to would-be aggressors everywhere that they may be able to get away with it too," Blinken told the Raisina Dialogue strategic affairs forum.

Speaking at the same strategic affairs forum after Blinken, Lavrov said it was "double standards" to question Russia's action in Ukraine when the United States cited a "threat to its national interest" to justify military intervention in various parts of the world, including the war in Iraq, air strikes on Libya, and the bombing of Yugoslavia during the Kosovo conflict in 1999.

Lavrov also said the question of when Russia will negotiate an end to the war should be put to Ukraine President Volodymyr Zelensky.

"Everybody is asking when Russia is going to negotiate...the West is continuously saying that it is not time to negotiate yet because Ukraine must win in the battlefield before any negotiations," he said.

At the G20, the United States and its allies called on member countries to keep pressuring Russia to end the conflict, but the G20 was unable to agree on a joint statement on the war due to opposition from China and Russia, which calls its actions a "special military operation" aimed at removing what it says is a threat to its own security.

The Russian minister went on to accuse Washington of "trying to militarise" the Quadrilateral Security Dialogue, a partnership between the United States, Australia, India and Japan that focuses on strategic issues in the Indo-Pacific region.

Earlier in the day Blinken had met with his counterparts from the Quad, as the grouping is informally called, and they issued a statement saying "the use or threat of use of nuclear weapons is inadmissible".

Late last month, Russian President Vladimir Putin suspended a landmark nuclear arms control treaty and threatened to resume nuclear tests.

During their brief exchange on the sidelines of the G20 meeting on Thursday, Blinken told Lavrov to end the war and urged Moscow to reverse its suspension of the New START (Strategic Arms Reduction Treaty) on nuclear weapons.

The Quad statement also took a barely disguised swipe at China by denouncing actions that increase tensions in the South China Sea, and the "militarisation" of disputed territories in the area.

China has denounced the Quad as a Cold War construct and a clique "targeting other countries".