MOSCOW, Dec 22 Reuters The rouble slumped to its weakest since late April past 72 against the dollar on Thursday as fears over the impact of sanctions on Russian oil and gas took the currency39;s losses this month to more than 15.

By 0740 GMT, the rouble was down 1.8 against the dollar at 72.25 , earlier hitting 72.3075, its weakest mark since April 29.

It also lost 1.6 to trade at 76.82 versus the euro , also a near eightmonth low, and shed 2 against the yuan to a near sevenmonth low of 10.28 .

The rouble is continuing its unrestrained fall, said Veles Capital analysts. Should the rouble consolidate above the psychologically important levels of 70 per dollar, 75 to the euro and 10 per yuan, it could open up new downside horizons for the Russian currency, they said.

Falling export revenues in recent months have been exacerbated by a European Union oil embargo that began in December, when an oil price cap come into force as well.

Brent crude oil , a global benchmark for Russia39;s main export, was up 0.3 at 82.4 a barrel.

Analysts expect the rouble to gain some kind of foothold next week when monthend taxes, which usually see Russian exporters convert FX revenues to pay local liabilities, are due.

Russia has been borrowing heavily in the final quarter of the year, on Wednesday selling 337.8 billion roubles 4.7 billion of OFZ treasury bonds.

Russian banks have been buying the vast majority of government debt, with sanctions preventing access for foreign investors,…