VILNIUS, Feb 16 (Reuters) - U.S. Defense Secretary Lloyd Austin said the United States was ready to defend the Baltic states of Estonia, Latvia and Lithuania if required, and will keep its military presence in the region.

"We are committed to Article 5, you can bet on that", said Austin, referring to the requirement in the NATO Charter that each member of the alliance defend each other if they come under attack.

Speaking in Tallinn after talks with Estonian leaders, he said the U.S. will continue to keep a "persistent, rotational" military presence in the region.

"The United States remains steadfastly committed to the freedom and sovereignty of our Baltic allies," Austin told the news conference.

The three Baltic States, neighbours of Russia and its ally Belarus, were once ruled from Moscow but are now part of NATO and the European Union.

Estonian Defence Minister Hanno Pevkur said his country is "working to prevent" it coming under attack if Russia is not stopped in Ukraine.

"Deterrence is the one key word here. This is exactly why NATO is coming up with new regional defence plans that will hopefully be approved in NATO Vilnius summit in July", said the minister.

Since 2019, the United States has deployed rotating groups of about 500 troops and equipment in Lithuania, and in December it announced a platoon of HIMARS artillery rocket systems and an infantry company in Estonia.

NATO has deployed three multinational battalions in each of the Baltic states since 2017, a "persistent" presence of rotating soldiers to serve as a trip wire for a larger response force should Russia invade NATO territory.

Germany has pledged reinforcements within 10 days in case of an invasion threat.

Austin in Tallinn reiterated the United States would be supporting Ukraine with military equipment, and said he expects Russia to continue heavy losses of its "ill-equipped and ill-trained" military personnel.

"This fight will continue to evolve, and we will do everything we can, working together, to ensure that we are providing them the means to be successful", said Austin.

"In terms of whether or not we can get equipment there in a timely fashion - this is something that we are working on each and every day".