President Vladimir Putin on Tuesday ordered construction sped up on a multi-billion-dollar spaceport in Russia's Far East that he said would break reliance on the Baikonur cosmodrome in Kazakhstan and launch future missions to the Moon and Mars.

Putin flew in a helicopter over the sprawling building site in Vostochny at a time when conflict with Ukraine, maker of Zenit and Dnepr rockets, is highlighting the fragility of Russia's dependence on former Soviet republics in defense and space.

Building a new launchpad on its own soil is central to Putin's effort to reform a once-pioneering space industry hobbled by years of budget cuts and a brain drain in the 1990s.

"Our own space infrastructure and modern network of cosmodromes ... will allow Russia to strengthen its standing as a leading space superpower and guarantee the independence of space activities," Putin said at Vostochny, near Russia's border with China.

Taking to task officials, Putin said construction was lagging behind by up to three months and the 6,000 workers currently at the site was half the number it should be.

"In the future, the capacity of the cosmodrome will be expanded ... to be used to realize program to explore the Moon, Mars and other space objects," he said.

Russia has already ploughed some 100 billion roubles into construction of the new spaceport, Putin said, to replace the Baikonur site that it has leased from Kazakhstan since the collapse of the Soviet Union in 1991.

Another 50 billion roubles is earmarked for the project through 2015, he said, hefty spending for a budget strained by the cost of annexing Ukraine's Crimea region and an economy stuttering under Western sanctions.

Despite Russia's current financial woes, a senior official tasked with overseeing the space industry vowed the country would not back down from investment in space.

"Despite the decrease in budgetary funds and the pressure on Russia from sanctions, this plan is unchangeable," Deputy Prime Minister Dmitry Rogozin told reporters.

In July, Russia launched its first new design of space rocket entirely built within post-Soviet Russia's borders from the northern military cosmodrome of Plesetsk.

A potential commercial rival to Arianespace of France and Californian-based SpaceX, a heavier version of the modular Angara launcher is designed to replace Russia's workhorse Proton rocket, which has suffered an embarrassing litany of failures.

While it is due to be tested at Plesetsk later this year, Russia hopes to launch the new rockets from Vostochny, where proximity to the equator would allow for a 20 percent heavier payload on launch vehicles.

(Writing by Alissa de Carbonnel; Editing by Ralph Boulton)