WASHINGTON (AP) — Leading U.S. CEOs remain supportive of some of President Donald Trump's policy initiatives despite his still-hazy plan for cutting taxes and recent actions by Trump that have intensified attention on federal investigations of his campaign.

The Business Roundtable, a trade association for CEOs, said Tuesday that the executives' economic outlook has reached its highest level in three years — a reading of 93.9, which suggests continued economic growth.

The association found in its survey of CEOs that plans for capital investment rose 4.6 percentage points since the first quarter, while sales expectations increased 0.5 percentage point.

Still, the executives' hiring plans for the next six months suggested a potential slowdown.

Jamie Dimon, CEO of JPMorgan Chase and chairman of the roundtable, suggested that the results reflect confidence in the prospect for overhauling taxes and in the administration's "commitment to creating a more favorable regulatory environment."

Dimon, speaking on a conference call with reporters, said "the urgency for tax reform couldn't be overstated."

The roundtable has been advocating lower corporate tax rates and a shift toward a territorial tax system, whereby companies would pay only on the income earned in each country. A majority of the organization's members have said they would delay hiring and investment plans if the tax overhaul pledged by Trump and congressional Republicans became stalled.

The Trump administration has released only a one-page outline of general principles on taxes, which stress lower rates for business and personal income. But its outline was so vague on key details as to raise doubts about the viability of rewriting the tax code this year while also passing a budget, raising the federal debt limit and overturning the federal health care law.

Much of Trump's attention in recent weeks has been focused on the investigations being conducted of his presidential campaign, including by Robert Mueller, a special counsel. Mueller was appointed after Trump fired the FBI director, James Comey, who was looking into ties between Russia and Trump's campaign. Comey is to testify Thursday on Capitol Hill.

Josh Bolten, a former White House chief of staff who is president and CEO of the roundtable, acknowledged that issues that distract from the Trump administration's policy agenda remain a concern but that the organization's survey results are a sign of "ongoing optimism for tax and regulatory changes."