* Deputy PM sees arguments to extend wheat export tax
* Says government to discuss tax next week
* Trader says tax is no longer needed (Adds details, quotes, context)
MOSCOW, April 3 (Reuters) - Russia may extend a tax on wheat exports beyond July 1, but is yet to make a final decision, Russian news agencies cited Deputy Prime Minister Arkady Dvorkovich, who is in charge of the sector, as saying on Friday.
Russia has imposed the duty on wheat exports since Feb. 1 in an effort to cool domestic food inflation as the rouble tumbled. The measure is set to expire on June 30, but traders have expressed concerns the tax could be extended.
"In favour of an extension, I see more arguments, but nevertheless a final position has not been taken," Interfax news agency quoted Dvorkovich as saying.
Dvorkovich also said he did not think it was expedient for Russia to cancel the export duty before July 1, when the 2015/16 marketing year starts.
Wheat exporters this week asked him to remove the duty ahead of schedule because, according to them, the rouble had strengthened against the dollar in recent weeks and officials had been optimistic about the 2015 grain crop, which the Agriculture Ministry expects to be up to 100 million tonnes.
Together with the stronger rouble and the ministry's grain crop forecast, prices on the domestic market are being depressed by high stocks in Russia's southern regions, which are key for exports via the Black Sea, Andrey Sizov, the head of SovEcon agriculture consultancy, has said.
The only reason why the government might want to keep the tax in place is its continuing effort to boost sales to state stocks, a trader, who asked not to be identified, told Reuters, commenting on Dvorkovich's point of view.
The Agriculture Ministry, which has 1.7 million tonnes of grains in state stocks, purchases grain on the domestic market every year in what is known as grain interventions.
While this year's grain-buying programme has lagged the original forecast, the ministry has set high wheat prices for the 2015/16 programme, fuelling hopes that the wheat tax would be removed.
According to Dvorkovich, the government will discuss the tax on wheat exports next week. Prime Minister Dmitry Medvedev previously asked his ministers to submit proposals by mid-April on a possible extension of the tax beyond July 1. (Reporting by Darya Korsunskaya and Polina Devitt; Editing by Alexander Winning and Alison Williams)