LONDON and KUWAIT (Bloomberg) -- Saudi Arabia told OPEC it pumped about 10.5 MMbopd last month as the kingdom sought to cap rallying prices by ramping up output, according to people familiar with the matter.

    The biggest member in the Organization of Petroleum Exporting Countries pledged last month it would raise output as consumers grow alarmed by crude prices, which have been bolstered by supply losses in some OPEC members and renewed sanctions against Iran. The June figure would represent an increase of about 500,000 bpd from May.

    The Saudis’ pledges don’t seem to have placated U.S. President Donald Trump, who resumed attacks on OPEC on Twitter on Tuesday for failing to moderate prices. The kingdom faces intense political pressure as prices reach levels that threaten economic growth, and as American sanctions on Iranian oil exports require replacement barrels to prevent a supply squeeze.

    U.S. oil futures surged past $75/bbl on Tuesday for the first time since 2014. They slipped toward $73 on Thursday as the Energy Information Administration reported a slight expansion in inventories.

    A Saudi Arabian supply surge was to be expected. A Bloomberg survey showed output jumped by 330,000 bpd last month, the largest increase since 2013. Saudi energy minister Khalid Al-Falih also said in Vienna last month that the country was increasing production.

    Saudi Arabia’s resolve to increase production is inflaming tensions with Iran, which stands to lose customers as sanctions take effect. Iran insists that production limits OPEC set in late 2016 still apply, and that any countries who increase beyond these levels are undermining the unity of the organization.