Russian President Vladimir Putin told Latvia's prime minister on Wednesday (March 28) a new border treaty was not enough to mend thorny relations between the two ex-Soviet states, but the step would be rewarded with new trade deals. Russia and Latvia signed a treaty on Tuesday (March 27) demarcating a frontier after a diplomatic row fuelled by Riga's claims over a tiny Russian border district caused a two-year delay. Relations between the two countries are marred by bitter memories of 1939, when the Soviet Union absorbed Latvia under a pact with Nazi Germany. Latvia regained independence in 1991. "I hope that your parliament deputies and the deputies of the Russian state duma will give a positive response to the governments of both countries for what has been achieved so far," Putin told Aigar Kalvitis, welcoming the first Latvian prime minister to visit Russia in his Novo-Ogaryovo residence outside Moscow. Moscow rejects Latvia's references to its Soviet period of history as an "occupation" and accuses the Baltic country of 2.5 million of discriminating against its 400,000-strong Russian minority. Latvia denies the charges. The European Union and NATO have welcomed the border treaty. But the document, which is still to be ratified by parliaments, has become a target of attacks from influential Latvian nationalists who insist on sticking to territorial claims. Putin made clear Russia was ready to back the treaty with economic perks. Latvia depends on Russian oil and gas and is a major transit route for Russian goods exported to Europe. Russia's monopoly Gazprom , which holds shares in Latvian gas company Latvijas Gaze, delivered 0.8 billion cubic metres of gas to Latvia last year. "We have been discussing long term agreements. For Latvia it is important to know the dynamics of supply and price structure (for gas) over the next five years. We discussed this, and we decided that we will have not just a one year deal, but a five year agreement. We also discussed the possibility of using gas storage facilities that already exist, and the development of new storage facilities. For this we need economic evaluation. So I can say the meeting was very constructive," Kalvitis told reporters after talks with Putin. Ahead of Kalvitis' visit, leading Moscow daily Kommersant quoted Latvia's foreign ministry as saying Riga was interested in joining a Russo-German project to build a gas pipeline under the Baltic Sea. Russian Prime Minister Mikhail Fradkov was quoted by local news agencies as saying the issue was touched upon during his talks with Kalvitis but gave no details. Kalvitis also held talks with Gazprom on Tuesday.