* Dollar tops 119 yen to its highest since July 2007

* Swiss voters reject boost to gold reserves, SNB welcomes outcome

* Aussie falls to 4-year lows vs USD as weak commodity prices bite

By Lisa Twaronite and Ian Chua

TOKYO/SYDNEY, Dec 1 (Reuters) - The dollar touched a more than seven year peak against the yen on Monday, while the Swiss franc slipped against the euro after voters rejected a plan for the central bank to boost its gold reserves.

Gold prices tumbled after Swiss voters overwhelmingly rejected the proposal in a referendum, adding to a broad rout in commodities that also sent oil prices to five-year lows.

Weaker commodities prices in turn raised fears that deflation would once again take hold in Japan, adding to divergent monetary policy expectations and keeping the yen under pressure.

The dollar rose as high as 119.03 yen on the EBS trading platform, its highest since July 2007.

"Options at 119 were taken out, with 119.50 the next target," said Kaneo Ogino, director at Global-info Co in Tokyo, a foreign exchange research firm, who attributed the dollar's spike to positioning as well as economic fundamentals.

"Oil prices are sharply down, so I think there are more fears of deflation," he said.

U.S. crude was down more than 2 percent on Monday, marking a five-year low of $64.10 per barrel, in the wake of OPEC's decision last week to refrain from cutting output despite a massive oversupply of crude.

Chinese official manufacturing data released earlier in the session gave investors no comfort, as it indicated slowing growth in the country whose demand is key to global commodity prices.

The dollar index, which tracks the greenback against a basket of major currencies, was steady on the day at 88.325, after earlier marking a four-year high of 88.451.

The euro was steady against the dollar at $1.245 and got a leg up against the yen from the dollar's rise, adding 0.3 percent to 148.01 yen.

The euro earlier jumped to a more than two-week high of 1.2040 Swiss francs from around 1.2018 late on Friday as investors who had been buying the franc against the euro, were forced to unwind those bets early on Monday. It was last up 0.1 percent at 1.2034.

The defeated "Save our Swiss gold" initiative would have compelled the Swiss National Bank (SNB) to boost its gold reserves to 20 percent of its assets, from around 8 percent currently, and banned it from ever selling the metal. That would have threatened its ability to defend a 1.20 euro cap on the franc.

The SNB said it welcomed the rejection of the popular vote, and reiterated its pledge to defend the cap.

"The result should of course temporarily relieve the pressure on the SNB's currency floor, albeit whilst doing little or nothing in our opinion to reverse the fundamental downward trajectory of EUR/CHF," said JPMorgan analyst Paul Meggyesi.

"At this stage the SNB needs to act on interest rates in order to create a pull factor to incentivize short-term capital outflows from the franc."

Weakening gold and oil prices provided no incentive for investors to buy commodity currencies such as the Australian dollar, and the downbeat China data did not help.

As a result, the Aussie was again probing fresh four-year lows against the dollar. It fell as far as $0.8416 from above 85 U.S. cents late on Friday, reaching a low not seen since July 2010, and was last down 0.7 percent at $0.8444.

(Editing by Eric Walsh & Simon Cameron-Moore)